By Carolyn Weise

When planning a water feature, many of us will imagine water lilies, lotus, cattails, and things like that. Then we think of putting koi in there. You couldn’t make more of a mistake if you added milk and cereal to the pond.

The different requirements are not even subtle. The plants require full sun, the koi need shade, at least part shade. The plants need calm water; the fish will do well in calm or fast moving water, the more filtration the better. The plants like to be left alone. The fish won’t ever leave them alone. What do you really want as a water feature?

Let’s look at water gardens: here is a piece of serenity, nature, easy to care for, and it will evolve over time. The water plants may be planted in a soil-bottom or set in pots on the bottom of the pond. There are a myriad of water plants and shallow-water plants, bog plants that would thrive in a sunny location with little or no care. They will invite a multitude of fauna to habituate your garden: frogs, newts, snakes, birds, butterflies, and all types of insects. There are fish that are perfectly suited to this type of garden pond without disturbing the plants. (Koi are not one of them.) Another beautiful thing about this type pond is no (or little) filtration is necessary. It will establish its own ecosystem in time.

The down side of water gardens is that they will become over-established in time and may need to be weeded out. Plants in water tend to grow much faster than those in the garden soil. They also develop enormous root systems making it difficult to separate or divide when the time comes. A natural pond will support this type of growth. A pond with a liner bottom will be easier to maintain and probably not as large, therefore should be more manageable. Some of the more aggressive plants would be Lotus and native species of water lilies. I also wouldn’t plant any tall cattails as they will crowd out all other plants in a short period of time. Planting in pots would be the easiest to manage.

Koi ponds on the other hand will be a high maintenance operation, no plants, and expensive fish. It is heavy filtration, special feed, careful husbandry, and water changes. There is very little to resemble the water garden other than the water. We will get into koi later, but for now, just know that there are major differences in these two gardens and decide which you really like before you add the fish.

MICROBE-LIFT thanks Tom Burton, veteran koi keeper and MAKC member for his invaluable advice and experience in pond building and his generosity in sharing with our consumers!

By Tom Burton

A koi pond is a purpose built habitat for those lovely fish we call “Living Jewels” and as such, differs from any other garden water feature. To introduce koi into other types of water features is usually a disaster waiting to happen and though one can get away with it for awhile, the end result is predictable. So, instead of doing what so many do, that is dig a hole, throw in a liner, add water and a few fish, and call it a koi pond, we want to help to get it right the first time. You only need to do it right once but you can get it wrong over and over.

This chapter will address building a koi pond with a liner but the only difference between a liner pond and any other is what’s used to contain the water. All other technical aspects are the same; bottom drains gravity feeding to a filtration system then to a biological processing station before being returned to the pond by recirculating pumps. But before attempting to build, read and heed the advice in this excerpt from the Mid-Atlantic Koi Club publication, From the Pages of MAKC News:

It seems that the more people that see koi, the more people there are that want to own one (or 10 or 50). But to make the transition from dream to dream pond, there’s an awful lot of information that must be read/seen/heard and assimilated before one has even a chance of success. So to preclude those would-be koi keepers from putting the carp before the horse, here’s a logical approach to what can be and in most cases is, a most rewarding and fascinating hobby.

The first rule is:

— DON’T BUY ANY FISH YET!!!–

Not only join a club but actively participate in all of its activities that you can make time for. Listen to any and all who will respond to your questions. You’ll get plenty of conflicting stories but after awhile you’ll be able to sift through the chaff and can start to formulate a well founded base from which to do your planning.

Go see as many ponds as you possibly can, all the while asking questions and storing the data for your future use. After awhile you’ll have some ideas on what your budget, real estate and imagination can handle so retrace your steps (or continue your search) until you find the THE pond, up and running, tried and true, that comes closest to what you think you want. Talk extensively to that pond keeper and find out from the beginning how he made it work and what were the mistakes and pitfalls along the way (that you can now avoid).

An ideal way to have the beauty of a water garden AND the distinct pleasure of a koi pond is to have both! – a lovely water garden tippling off into a koi pond. The plants can’t be disturbed (or eaten) by the fish because the fish can’t get to them and the fish can be viewed in all their glory, unfettered by pots and plants.

by Tom Burton

Perhaps one the most difficult but truly critical aspects of building a koi pond is where we put it. The whole point behind doing this in the first place is to be able to see it and enjoy it so if we put it off somewhere in the “back 40” we might as well save ourselves the trouble. Ideally, the pond will sit where we can see it from the house all year ‘round. We may need to remove an old concrete patio or demolish or remodel a deck or even transplant or remove some existing plants or trees, but it will be worth it in the long run. Deciding just where it will go and what it might look like will take some imagination but that can be helped by using a rope or garden hose or even spreading lime to outline the pond’s perimeter on the ground. Then, viewing it over several days from many angles from rooms in the house as well as from the surrounding property will help in deciding the ideal spot. And finally, while we’re at it, we may decide to replace some windows with a larger expanse of glass so as to incorporate the outdoors with the indoor living space. This is an excellent way to heighten the enjoyment, particularly if the pond is close enough to the house that we can walk to that window and actually see into the pond and watch the kaleidoscope of colors as the fish swim in ever changing patterns.

by Tom Burton

Once the “where” is decided, we need to determine size and depth.

An ideal pond for the average hobbyist is between 23 and 25 feet long by 12 to 13 feet wide and 3 to 4 feet deep. (The 1% or less of koi hobbyists who want to grow jumbo koi or keep fish primarily to compete in shows with, will want much deeper ponds of 6 to 8 feet). This size pond can accommodate 15 to 20 mature fish (24 to 28 inches) giving them plenty of room to exercise and, will not look overstocked and crowded. Here’s how we calculate the volume of water in this pond: Length x width x depth = cubic feet x 7.5 gallons per cubic foot = volume in gallons. So, 25 x 13 x 3 x 7.5 = 7312 gallons. However, this is only an approximate figure as the pond will not normally be a perfect rectangle and the shape may be more freeform. We will only know the exact volume of pond and filtration system upon filling the feature and metering the input. And it’s extremely important to know the exact volume.

Keeping the width of the pond to less than 13 feet is so that when we have to catch a fish, for whatever reason (and there will be reasons), we need to be able to extend the net from one side to the other and any net and handle longer than about 12 feet is quite unmanageable. (See section on catching fish).

by Tom Burton

The next step is to lay out the pond perimeter using powdered lime or a rope or hose to see what this thing is really going to look like in the spot you’ve chosen. Again, it’s probably good to leave this for a couple of days to see if that’s what you really had envisioned. Then, start digging.

If you live in an area where ice might be a problem, slope the sides about 20 degrees so the ice can slide up as it expands instead of straight out (and through your liner). Dig out the trench for the 4″ bottom drain pipe and run it all the way to where the rest of the filter system will go. If a straight shot is not possible, use 45-degree elbows to raise or turn the pipe rather than 90’s. The fewer bends the better. Put the bottom drain and all the pipework in place to check all the measurements before gluing. It’s a good idea to cover the whole top of the drain to keep dirt out. If the drain is sitting on firm virgin clay/soil, there’s no need to set it in concrete. The weight of the pond water will hold it steady.

Returns from the pump and filtration system to the pond are usually via a waterfall and a couple of through-the- liner bulkhead fittings that allow for the creation of a current by using directional “eyeball” (spa) fittings or 90 degree Fernco elbows with the clamps removed (so the fish don’t hurt themselves) and glued to the pipe out of the bulkhead. Don’t be afraid of the through-the-liner returns. Just be sure to tamp the backfill around each pipe so they’re in a solid setting. It usually takes two people to install them and only go arm’s length down the side – one person holds the outside of the fitting outside the pond (male threaded) while the other tightens the nut that sandwiches the liner against the flange (female threaded) for a water-tight installation. A bit of aquarium-safe adhesive wouldn’t hurt either.

Tip: Inch-and-a-half PVC, schedule 40, is good for most water transfer functions. However, if the run is longer than about 15 feet, 2″ works better by reducing flow resistance. If flexible PVC is used, be sure to use the PVC cement made for it. Also, always use PVC cleaner before gluing (a clear one is available if you don’t want to see all the typical blue around joints).

Tip: Fernco couplings make pipe joints simple. This is a rubber coupling with stainless steel clamps and comes in many configurations and is available at home centers and plumbing supply houses. After installation, check for tightness periodically if used near pumps. They have been known to loosen, detach and allow depletion of an entire pond.

Tip: Skimmers are a really “nice-to-have.” Either the inexpensive (about $40) aftermarket one or a swimming pool type that installs in the liner just like it does in a liner swimming pool. They keep the surface looking great and both require a pump to operate (external is best – 2,000 to 2,400 GPH).

You’ve already decided whether you’re going to have a partially raised pond and what that structure will be made of and look like, or you know what type of stone you’re going to use around the place. The rule here is to hide the liner and the plumbing. The water level should always be a little above the exposed liner inside the pond. This means that the liner must not only go under rocks placed around the edge of the pond, it must come up behind them as well. To accomplish this, a shelf an inch or two below the intended water line is in order (remember, you know where the water line is going to be because of the levels shot with the transit). Hiding that back edge or tip of liner can be accomplished by using overlapping rocks, plants, decking, you name it (see diagram). Here’s where your imagination comes to play. Just don’t let it show either inside the pond or out. Decide how the excavation at the top perimeter of the pond should be done to arrive at the look you intended. It’s a good idea to steer clear of a necklace or swimming pool look except maybe for a partially raised pond.

Tip: The edge of the pond should be slightly higher than grade so that rainwater doesn’t flow into the pond.

Now’s the time to check the dimensions of the pond again and calculate the size liner you’re going to need. Length plus 4′ plus (depth x 2), and width plus 4′ plus (depth x 2). That 4′ in each direction is to give you 2′ overhang all around. Thus a pond 25’ x 13’ and 3′ deep needs a piece of liner a minimum of 35’ x 23’ plus any for bog garden, streams or waterfalls. If the stones you’re using are more than 18″ wide, you will need to add liner accordingly. The rule of thumb is, if water is going to be there, there must be a covering of liner AND a lip at the back to contain it. Don’t forget to include a planned stream or waterfall. They need to be lined as well and the water contained on the sides (with the liner hidden of course). One contiguous piece for everything, to include the water garden if that’s in the plan, makes it a lot easier but there is an EPDM bonding material that does well when applied properly. Or, there is an EPDM tape that will work if applied with care and correctly. There are some good diagrams and examples of perimeter treatment in the Tetra Encyclopedia of Koi and though this book is an excellent reference, it’s rather dated, particularly in filtration, so check with other folks before accepting the material as gospel. The fundamentals are all there but technology and new developments have passed it by.

Now the hole is perfect and its time to lay padding for the EPDM. Old carpet works well, as does sand or carpet padding, almost anything that will give a bit of cushion and help the liner resist puncture from underneath. Once that’s in place you’re ready to lay the liner. And since its pretty heavy, fellow club members or friends are needed for this operation. One method is to lay the whole liner out and roll it up from the sides to the center lengthwise then tie it in a few places to facilitate carrying by you and your friends. Then march single file through the hole, placing the liner properly lengthwise, and then roll it out from the center and up the sides. Another way is to get six people to hold it out over the hole then gradually let it drop into place. Once it’s in the proper position, smooth out the bottom over the hole for the bottom drain, mark the hole with a Magic Marker, then cut the hole in the liner as neatly as possible with a utility knife. Then apply a fish friendly (aquarium safe) adhesive/caulk between the liner and the bottom drain, then on the collar that will sandwich the liner and the bottom drain together. With the collar in place install the screws or whatever fasteners came with the drain trying to apply equal tightening all around. Wait for that to set-up according to the directions for the adhesive, then proceed to lay the liner so as to avoid as many folds and wrinkles as possible (this the major down side to using a liner – some folds and wrinkles can’t be avoided and will harbor crud). This was my saddest day as I couldn’t imagine getting that huge sheet of rubber to flatten out and look like anything – but of course it mainly did and with gorgeous fish swimming around I don’t notice it anyway. As the pond slowly fills it’s possible to work even more wrinkles out as the weight of the water starts to work in your favor. It’s not a good idea though, to stretch the wrinkles out by letting water act as air would in a balloon – this ends up thinning the liner. Some folks have filled their pond, left it sit for a few days, then pumped it out and started the wrinkle removing process again as they refilled. They say it helped. Also, the use of 6″ EPDM tape can help flatten and seal major folds. The anti-vortex domed top for the drain should be set about 1 ½” off the bottom.

Tip: When filling the pond, water should be metered so you will know FOR SURE how much is in there AND in the entire filter system together. You’ll need this info if/when you must treat for parasites or other baddies as dosages are based on water volume (and no one I ever heard of has gotten away without some).

Tip: DO NOT CUT excess liner until you are SURE it isn’t needed. This is a lesson learned the hard way by too many of us.

Now to the filtration system: At this stage you should have the system all hooked up and in place or have all the necessary parts on hand. You’ve kept the water in the pond from running out the drainpipes by closing the knife valve for each. Look at the attached filter diagram as only one of many ways and means to arrive at the same end; good water quality. The filter system is the key to that and if we don’t have good water quality, we can’t keep koi (very long) – period. The system incorporates bottom drain to settling chamber to mechanical filtration to biological processing to pump to pond. It doesn’t matter what the containers look like, or what their shape is as long as they hold water and don’t lose their shape when filled. The settling chamber won’t work if we feed it too fast. The mechanical filter won’t work if all the water isn’t forced to travel through the filtration media. Likewise, the biological processing station won’t work if the water can go around the media you’ve selected as the home of the good guy bacteria. Water will seek the least line of resistance and all of your efforts will be for naught if it doesn’t go THROUGH the media. Also, match the media to the type container. Brushes do well in round, or straight-sided square or rectangular containers. Ribbon type media goes in either as well. Ribbon material will try to sneak out purge drainpipes if you don’t contain it (say in nylon drawstring laundry bags or by having a grate at the bottom of the container). However, these are just a few of the potentials for media so ask and look around. They are ones I’ve used successfully though.

Now we can start up the pump and test our recirculating, gravity fed system. The pump should obviously be outside the pond and move 2,000 to 2,400 GPH. It normally doesn’t have to create much head or pressure as water falls should neither look nor sound like Niagara Falls. The effect should be soothing, not kinetic or frantic but that’s a personal thing I guess. Most of the water being pumped will go to the through-the-liner returns to create the current we mentioned earlier. The fish love it and the crud is moved to the bottom drain where it belongs. There are several choices of pumps and any one that uses around 3 amps and is quiet will do just fine. Most have 1 ½ ” input and output connections. If you’re going to use 2″ pipe from (and/or to) the pump, just use a 1 ½ ” to 2″ coupling. Installing a ball valve (Teflon ones are best) on the output side of the pump for complete control, and a flow meter that displays 20 to 80 GPM, are highly recommended.

Tip: Amps x voltage = watts x 24 hours divided by 1000 = kilowatt hours (KWH). Example: 3 amps x 120 volts = 360 watts x 24 hours = 8640 watts divided by 1000 = 8.64 kWh x rate charged by the electric company per kWh (mine is 15 cents) = $1.29 per day to operate the pump (or $38.88 per month).

Tip: Union couplings on the input and output side of pumps make for quick disconnects.

You’re up and running now and have used some type of dechlorinator to neutralize the chlorine in the water and are ready to add a few fish that will provide the food (ammonia) for the good guy bacteria to get started. Remember that our biological processing station is only RE-active and never PRO-active so it always has to catch up to any increased bio load (so we never want to add a lot of fish all at once).

Tip: Call your water company and ask if they use chloramine to get rid of bacteria. If they do, you need a neutralizer that attacks that specifically. Just read the label on the product.

(Carolyn says: Aqua Xtreme neutralizes both chlorine and chloramines and removes ammonia and heavy metals, etc.)

Tip: An ultra-violet sterilizer is the best way to get rid of suspended algae (which makes our water green). The wattage needed depends upon a lot of things, such as nitrate in the water and hours of sunlight on the pond (algae is a plant after all and needs food and sunlight to thrive). A 40-watt UV with water flowing through it at 900 GPH, works very well for most ponds (4000 to 6000 gallons). If you need more power and water is run through two 40-watters one after the other in sequence, you can increase the flow to 1800 GPH (or 3 to 2700 GPH, etc.) Those are figures I know to work but the hobby has more art to it than science so a little deviation either way probably wouldn’t matter. A branch off of one of the returns or even placed in a return line, can supply the water but you’ll need to know what the flow rate is. Installing a flow meter in the line will take care of that and the ball valve on the line after the pump will be your control. The alternative is a separate small submersible pump (of the type without oil in it) picking up water from the processing station or the mechanical filter and pumping to the waterfall or even from one container or section to the other, will work.

by Tom Burton

They’ve just discovered an eleventh stone tablet somehow missed by Moses. The inscription reads, THOU SHALT NOT BUILD A KOI POND WITHOUT A PROPER BOTTOM DRAIN. Imagine that. Even then they knew. The ideal set-up is to have the drain(s) CONTINUOUSLY gravity feeding to the filter system(s).

Why gravity feeding? So the big stuff stays as much intact as possible as it enters and settles in the first phase of the filtration system, appropriately called the settling chamber.

Why continuously feeding? Because crud lying static in the bottom of the pond and in drain pipes waiting for someone to purge it, quickly becomes anaerobic (lack of oxygen), and poses a dire threat to the health and well-being of our treasured friends. This becomes even more acute during the winter if the filter system is shut down. Why?

Follow this line of reasoning: If the water is not being re-circulated and stands relatively still, where is the worst water in the pond? AT THE BOTTOM. Where do fish stay in the winter? AT THE BOTTOM. If we don’t run our systems we force the fish to live in their own, continually worsening sewer. No wonder so many folks dread deadly springtime. AND, to absolutely compound matters, starting up from scratch each spring means all the pain and agony of “New Pond Syndrome” every year. Ugh!! They say it takes a couple years for a biological processing station to become mature and although arriving at that conclusion was not done scientifically, experience sure bears that out.

by Tom Burton

They say that the key to keeping koi is water quality. Then the key to water quality is adequate and appropriate filtration.

Any filter system (and the emphasis is on system) should include the following four, essential elements:

Bottom drains – A 4,000-6,000 gallon pond might get along fine with just one bottom drain if constructed so sediment was kept moving toward it. Ponds above 6,000 gallons should have at least two bottom drains gravity feeding to two separate filtration systems. If two or more are used, they should never be connected by a “Y” but taken all the way to separate (or one very large) settling chambers in at least 4″ schedule 40 or 80 PVC pipe. Four inch drains should have an anti-vortex dome that is supported by a central pedestal and not the type supported by legs at the edge of the dome. They become traffic jams which eventually stops flow. Drains should gravity feed to the filter – if you pump to a filter you puree all the poop and stuff making filtration – spelled EXTRACTION – more difficult.

Tip: A word on gravity feeding. The basic rule is, water will always seek its own level. If you place two containers (or even more) side by side (such as a pond and a settling chamber) and run a pipe from one to the other(s) anywhere below the water line, and fill them with water, the water level will even out from one to the other. If we pump from one, the water from the other(s) will flow to compensate and that’s how a gravity flow recirculating system works. As long as the pump is running, the filter system water level will always be slightly below pond level as the pond water is always trying to catch up. How much difference depends on the flow rate of the pump. The higher the output of the pump, the lower the water drops in the filter system containers. Example: 2400 gallons per hour (GPH) will drop the level about 1 inch. Note: A new (slick) 4″ PVC pipe can carry about 3500 GPH by gravity. The flow rate will reduce as the pipe starts growing things inside.

Settling chambers – The most efficient is called a vortex (whirlpool). Water enters on a tangent about two thirds of the way down the side of the container, causing a swirling motion forcing the larger pieces of crud to move out to the sides where gravity draws them down to the bottom where the purge line enters the cone shape of the purpose built container. When we see a build-up of debris, we just pull the knife valve in the 3″ (minimum) purge line and get rid of it to waste. For most Koi ponds, this container should be a minimum of 40″ in diameter and 40″ deep. The point is to slow the water down enough for the heavy stuff to drop out and any smaller container is ineffective when pond water flow rate is at the typical 2000-2400 gallons per hour (2400 GPH is maximum for a 40″ vortex). The rule of thumb is, the larger the vortex the greater water flow we can have and still accomplish the same result.

Mechanical filtration – This is where we actually strain or extract or trap or take something out of the water. We actually want particles to cling to whatever we place in the path of the water. The choices of material are numerous but my choice is cylindrical (usually 4″ in diameter) brushes with a stainless steel core and bristles of nylon or other similar synthetic material. It’s best to buy the thick, good ones as they’ll stop more stuff and they never wear out. They come in various lengths to suit your needs and can be used in up-flow, down-flow or horizontal applications. You’ll want at least four rows, each one slightly enmeshed or overlapped with the other from side to side. And with brushes, more is better. They can be hung in place with dowels or metal (non-rusting) rods. However, they must be cleaned from time to time and because we’re not asking them to perform any biological function, a garden hose and chlorinated water is okay if flushed away from the system (chlorinated water will kill the good guy bacteria in the biological processing station).

Biological processing – Here’s where the chemicals you can’t see such as ammonia and nitrite, are eaten by “good-guy” bacteria provided by Mother Nature. Remember, every surface under water anywhere in the pond – this means streams, waterfalls, the sides of the pond, anything under water – is a place for “good-guy” bacteria to reside and work for you. But because we usually have too many fish in too small a body of water, this surface area is insufficient to do the job. So – what most of us do is provide a container of some kind of material outside the pond, on which the bacteria can colonize. What kind of material? Ask ten different people and get ten different answers. The rule of thumb is to get the most surface area for the smallest volume. I like Japanese or domestic matting or the ribbon-like media for their light weight and ease in cleaning (even though we give this container the cleanest possible water, over time crud will accumulate and we’ll have to clean it). I don’t like lava rock or any kind of gravel/aggregate because it tends to clog and channel and is tough to take out of a container and try to clean. (How do we know if our processing station is doing its job? Test the water. Inexpensive test kits for ammonia and nitrite are readily available and should be used routinely and should always show zero contamination). It’s from this processing station that we’ll pump back to the pond and create the gravity flow/recirculating function.

Tip: Ready made filter systems are available but size is critical. Be doubtful of anyone who shows you a 2′ x 2′ x 3′ box and tells you it will take care of 6000 (or whatever) gallons. This might work if you only want a couple of fish. Ask instead, how many mature, 24″ fish, being fed normally, that the filter system can support. There is no formula and little science to help us decide on size and shape so talking to experienced koi keepers is the best approach.

Tip: You can have as many fish as your filter can support but, a crowd looks like a crowd. Fifteen, 24″ fish in a 25′ x 13′ x 3′ pond looks great. Fifty, 12″ fish looks like rush hour on Times Square.

In addition to selecting a site for the pond, you need to decide where the filter system will go. It can go most anywhere -out in the woods, around the corner of the house, maybe in the garage – but it should either be concealed or suitably camouflaged so as not to intrude in the beautiful setting you’re making. The use of a surveyor’s transit will come in handy to make sure the water level in the filter system will be the same as the pond. These can be rented at equipment rental places and this is critical to the efficiency of a gravity fed recirculating system.

by Tom Burton

If the bottom of the pond has been sloped a bit to the bottom drains, most of the sediment will make its way from the pond to the filtration system without any help from the koi keeper. The returns through the sides of the pond from the filtration system will produce a bit of a current and keep particulate suspended and headed for the bottom drains or skimmer. However, there are routine maintenance tasks that need to be carried out periodically.

  • Purging of the settling chamber. Heavy material will settle to the bottom over time (the amount depends upon the fish load and many other factors) and will need to be drained to waste. This is accomplished by turning off the pump, closing the knife valve in the drain line to stop the water from entering from the pond, then opening the chamber purge line knife valve and letting the chamber empty. Then reverse the procedure to get back up and running.
  • Cleaning the material used in the mechanical filter. This is where lighter material that didn’t settle in the first chamber is stopped – “filtered” – from the water. There is a variety of materials used to accomplish this but no matter which is chosen, it must be cleaned from time to time. The use of a powerful stream from a garden hose works well and since we’re not asking this material to work as a surface for the “good guy” bacteria to live on, we don’t need to be concerned about the chlorine killing them off.
  • Cleaning of the catch-basket in the skimmer. The dust, pollen, leaves, etc. that end up here, need to be gotten rid of as needed so the water flow is unimpeded.
  • Cleaning of the media in the biological processing station. The water going to this part of the system should be as clean and free of particulate matter as possible so that the cleaning of it is necessary only rarely. We don’t want to destroy or reduce the numbers of “good guy” bacteria that take up the ammonia and nitrite for us. So, this cleaning can safely be done in pond water or a small portion taken at a time and hosed off, then another portion at a later date, etc., until the job is finished.

(Carolyn says: We have Nite-Out II to recharge filter media after cleaning.)

  • Water testing. At a bare minimum, tests for ammonia, nitrite, and KH should be done frequently (weekly for the first several months then maybe less frequently but routinely and among the first things if there appears to be a problem). Ammonia and nitrite readings should always be zero and KH should always be 100 ppm or above.

(Carolyn says: Did you know Microbe-Lift has various sizes of KH Bio-Active Booster to raise the KH?)

  • Water changes. Routine changes of 25% per week in the summer and 10% in the winter are recommended. The primary reason is to replenish the mineral content in the water -vital to fish health. Also, it is the first line of defense if there appears to be a problem – even up to 50% when toxins such as chemicals from lawn or tree and shrub treatments are suspected. Just be sure and neutralize the chlorine or chloramine.
by Tom Burton

Some folks have said I seem to have a knack for netting fish. Maybe so, as it seems to come very naturally. But when asked to describe my method (or write about it) it’s sort of like trying to tell somebody how to ride a bike or learn to drive; there’s no substitute for experience. However, to shorten the learning process, here’s my methodology, for whatever it’s worth.

A 32” net is a “must” no matter what size fish you’re going after. The length of the handle depends upon the size of your pond, your strength (you’d be surprised how heavy and cumbersome that thing becomes with over a five foot handle), and whether or not you’ve got a “herder” to help keep the “target” fish in your reach. By the way, the herder never attempts to catch the fish.

I keep total concentration on the target fish, and the position of my net, all the while segre­gating the target. Don’t get distracted. Move very slowly. Don’t stress the other guys either. Let’s keep everybody cool and calm.

Start advancing on the target from the bottom of the pond. You want him to rise toward the surface (it would do you no good to have him in the net at four feet – he’d just swim away as you started your ascent.)

Once near the surface, the net should be moved under the fish and slowly raised and turned toward the side of the pond to corral the fish. Then, slowly raised and turned up to the surface with the fish “free” in the water in the net. NEVER lift a fish out of the water with a net as you may injure a scale or fin inviting a bacterial invasion in the broken mucus immune system.

At your side you have a large pan, such as we use at shows, which you can now, after having brought the fish hand-over-hand closer to you, dip into the net and allow the target to gently enter. Or you could use a sock net for the transfer but – NEVER lift a fish out of the water in the large net as it’s very likely to cause damage to fins or scales.

Sounds easy doesn’t it?

A couple other “nevers”:

If the fish darts past your net or jumps out of it, never give chase. Just start the process over again. Never stab the net at a fleeing fish. Suppose you nailed it to the side of the pond. That’s like taking a block from a Dallas Cowboy – survivable, but sometimes bringing injury and always bringing discomfort.

The old saw about “If at first you don’t succeed” comes to mind about now. Practice. And in the meantime, happy hunting.

By Carolyn Weise

The benefits of a waterfall are many, as are streams, however they are generally chosen for aesthetic purposes. The sound of running water, the natural feel of water running through the garden, and the reflection of birds, sunlight and flowers have a relaxing effect on our blood pressure and other senses. What is not as well known is the benefit to the pond. The moving water actually gathers oxygen as it travels over rocks and splashes into the pond. Of the waterfall and stream, the stream is probably the more efficient oxygenators of the two. But the waterfall remains the more popular. Let’s first look at construction of a waterfall.

WATERFALLS: When building a waterfall, it is helpful to consider water direction and flow into the pond, as it is to be a big part of the circulatory process. A healthy pond does not have ”standing” water, but is continually moving every part toward the drain and filters to be cleaned and refreshed. Therefore, the angle you choose and the placement should be farthest from the skimmer and filter intake unit (bottom drain). The height of the waterfall will depend upon the size and surface area of the pond. A tall heavily splashing waterfall will empty a small pond quickly, therefore too much splashing should be avoided. By proportioning the falls to the pond you will have a better system and fewer problems. Almost all pond leaks can be traced back to improperly constructed waterfalls.

A reservoir at the top and bottom of the waterfall will not only help contain the water, it will also offer a place for more rocks as an aid in oxygenation. Plants can be added to the top of the falls. The first step after determining the site for the waterfall is to build a foundation, for which cinder block or concrete blocks work well. This will be set in place, mortared to smooth out any rough edges, and lined with EPDM liner. It can then be ½ filled with sand and smooth stones, leaving a shallow pool for gathering water. There is nothing pretty or natural about water spurting out of a PVC pipe. All liner and pipe work should be covered by rocks, and the liner must be higher than the water level to prevent future leakage.

When adding a waterfall to an existing pond, it is best to overlap the liner into the pond rather than to try tucking them together. The water will “wick” out between the two pieces of liner if they are together. It is also very difficult to glue two pieces of liner, especially if one is already used, without leaks. Arrange the waterfall rocks so they overhang the pond for a more natural look and match the waterfall rocks to the ones used in constructing the pond.

Tip: Use a variety of rock sizes, rather than uniform size, as it will look natural if there are, for example, large boulders and very small rocks together.

STREAMS: Streams are incredibly useful as bog systems, vegetable filters, oxygenators, and are attractive to wildlife. A woodland-type stream can be made with EPDM liner and muscle power.

Bring in dirt, or dig and move, to build up an area, 15-30’ long and 5-6’ wide. Use stones to support the dirt along the sides and hollow out individual pools in the stream bed. Each pool should be 3’ deep and 4-5’ wide. Leave partitions of dirt between them, and have each one lower than the one before, going down toward the pond. Start at around 4’ high for the first one. The partitions between each pool will be spillways from one into the next.

Then stretch a liner over the entire stream, leaving 2’ on each side, the top and bottom. Mold it into each pool carefully, and ½ fill with sand and a layer of smooth stones. Place a flat rock on the spillway, at the waterline for each pool. This will assure a good flow. Be sure to use a level and have the sides higher than the spillway, or the water won’t go where you planned. The sides should be 3-4” above the spillway and waterline levels to prevent water loss.

Then tuck in the liner, in and under rocks along the side of the stream. The water line will enter from the top of the first pool, and should be hidden by rocks. It must be secured so the water cannot go anywhere but into the first pool. Bury the line back to the filter or pump.

Plants along the stream will add to the natural look and those used in the stream will become vegetable filtration for the pond!

Tip: Install knife valves for winterizing, or diverter to underwater return, so the stream and waterfall can be shut off and prevent super-cooling the pond when temperatures drop below 50ºF.

By Carolyn Weise

A bog is the term for any water retentive garden, wet, spongy ground, small marsh or swamp.

In pond and water gardens today we loosely use the term bog as a filtration device for our ponds. It is a man-made shallow pond, ¾ filled with soil or sand, topped with rocks and planted with water loving plants. The water is circulated through this bog from the filter and back into the pond. In certain pond construction it is simply used as an in-pond device to make the pond more natural looking, and as a glorified planting area (rather than using potted plants the plants are planted directly into the media and allowed to spread freely within this area).

Some water gardens have filters for the bogs consisting of French drains beneath the rocks, like undergravel filters in a fish tank, to prevent buildup of anaerobic bacteria. In these conditions, the plants are used to filter nitrites from the pond and convert them to nitrates. Others have built “out-of-pond” vegetable bogs to filter the nitrites by having water flow from the filter, through a container of plants and return to the pond. These will be built out of various waterproof containers and may not be permanent fixtures.

Ecological Laboratories thanks Dr. Carl Webster for so graciously donating this excellent resource on protein so readers will be better informed of their fish’s needs.

A) PROTEIN AND PROTEIN QUALITY IN FISH FEEDS

By Carl D. Webster, Ph.D., Aquaculture Research Center, Kentucky State University

Nutrition involves the processes by which an animal is provided with nutrients needed for maintenance, growth, health, coloration, and reproduction. A nutrient is defined as an element or compound of dietary origin which is necessary to support the life and well-being of an animal. Nutrition concerns all aspects (assimilation, digestion, absorption, and utilization) of a food. There are several broad classes of nutrients in a food. These are proteins, lipids (fats), vitamins, minerals, carbohydrates, and energy. Since protein is generally the most important constituent of a fish feed, we will begin our discussion of fish nutrition with a look at protein and protein quality.

Protein is not only the most important constituent of a fish diet, it is generally the most expensive (compare the prices of a pound of steak to a pound of rice). Proteins are made up of amino acids linked together by chemical bonds. There are 20 amino acids which are common to most proteins, and 10 of these are essential for normal growth and health of the fish. These 10 essential amino acids are called, oddly enough, essential amino acids. They are: arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. There are three types of proteins. Fibrous proteins are highly indigestible and include collagen (found in connective tissue and bone), elastin (found in blood vessels), and keratin (found in hair, hooves, scales, and feathers). A second type of protein is the contractile proteins which are found in the muscle. These proteins are highly digestible and are found in the flesh of all animals. The third group is represented by globular proteins which are found in hormones, enzymes, and blood.

Proteins serve many functions in fish. They are components of bones, skin, organs, and muscle. Generally, about 70% of the total weight of the fish is made up of protein. Like humans, fish cannot make the essential amino acids in the body. Therefore, fish need to have a dietary source of proteins as the source for essential amino acids. As the protein is broken down in the digestive tract, the amino acids that were once linked together are separated into individual amino acids, called free amino acids. These free amino acids are carried through the blood and travel to the various organs and tissues where they are rejoined together to make new proteins. If a fish gets too little protein in the diet, growth of the fish is reduced and, in severe cases, weight is lost. Feeding fish too much protein in the diet is not wise because protein is expensive and the cost of the feed will be higher than needed, and the excess protein will be used as an energy source. Lipid (fat) is a much better, and cheaper, source of energy for fish.

Fish require a certain percentage of protein and a certain level of essential amino acids for proper growth. These requirements depend upon the size of fish, water temperature, culture conditions, daily feeding rate, stocking rate, and species of fish. The last factor is different than in most animals. One breed of cattle requires the same protein level as another breed. Likewise, all breeds of dogs require the same protein level in their diet. This is true for goats, cats, hogs, etc. However, each species of fish have their own protein requirements. Thus, koi have a different protein requirement (actually essential amino acid requirements) than do largemouth bass, or carp, or tuna. This makes feed formulation for fish quite interesting.

Protein quality, or the nutritional value of proteins, is based upon the amino acid composition of the feed ingredients, specifically the essential amino acid content, as well as the availability of the amino acids. The percentage of protein that can be digested by a fish determines protein quality. For instance, poultry feather meal is an ingredient with a high percentage of protein (80%) and is not very expensive. Thus, one might think that a fish diet could use a high percentage of this ingredient and save the producer some money. However, this is not the case. Poultry feather meal is very poorly digested by fish and thus has a very poor protein quality value. However, if the feather meal is hydrolyzed (broken down) during processing, the protein quality is improved, but so is the cost of the ingredient.

Generally, marine fish meal represents the highest quality protein source used in fish diets. Marine fish meals can contain between 60-75% protein, of which between 80-95% is digestible. Poultry by-product meal is an animal-source protein ingredient that has attracted much attention from nutritionists and is used in numerous feed formulations as a partial or total replacement for marine fish meal. Soybean meal, cottonseed meal, corn gluten meal, soy protein products, and distiller’s and brewer’s by-products are commonly-used plant protein sources. For koi and goldfish diets, additional ingredients may be added to the diet to enhance color and health of the fish, such as algae meals, yeast, protective and chelated forms of vitamins and minerals, and ingredients that enhance color of the fish.

Thus, when one evaluates a feed, it is not enough to know the percentage of crude protein. One must know if the ingredients supplying the protein have a high protein quality that is digestible to the fish. Only by meeting these two criteria can a fish feed be considered adequate to meet the protein requirements of the fish.

B) FEEDING BASICS- TEMPERATURE RELATED FEEDING GUIDE

By Carolyn Weise, as per reported koi hobbyist generally accepted practices.

Under 50ºF No Feeding recommended.

50-65ºF Cold Weather Wheat Germ recommended- starting at 1-2x/week at

50ºF, gradually increasing to daily, then by 60ºF twice daily.

66-85ºF Summer Staple, Growth Food, Color Enhancing Food- feed small Portions 3-6 times daily.

Over 85ºF Cut back on feeding regimen. Feed 1-2x/daily as fish cannot Metabolize at high temperatures or low temperatures. Cold Weather formula can again be used for easier absorption.

Over 90ºF No feeding recommended. Any uneaten food will add to organic load and oxygen depletion in the water. Fish will begin to die.

Ecological Laboratories, Inc. thanks Dr. Julius Tepper for generously offering his broad knowledge of fish care in presenting this information.

QUARANTINE

By Carolyn Weise, Ecological Laboratories, Inc. and Julius Tepper, DVM, Long Island Fish Hospital, Shirley, NY

When I started collecting koi, I knew nothing and was blissfully ignorant. I think “blissful” was my key word here. And, why not? I was engaged in a prestigious new hobby, one with excitement, extravagance, danger. Back then, we had the Aeromonas and Pseudomonas infections to watch out for! We had parasites! We even had thieves who stole into peoples’ yards at night and stole their koi!

“Ignorant” didn’t mean much to me at that time. Nor should it. But in 1998, the koi hobby was irrevocably changed—forever. No longer can I (or any other koi collector) afford to be blissfully ignorant about quarantine when it comes to adding new fish to our collections.

The word itself has had far reaching effects. Shows have changed also. No longer do we have the luxury of viewing all the same-size category showa in one tank, but the judges now have to go the length of the showroom floor to judge the merits of one fish against another in order to protect the contestants from communicable and fatal disease. In 1998, immediately following a koi show at Hofstra University, NY, many ponds were wiped out due to a new disease, yet unnamed and undiagnosed. I bought three fish at that show and was one of the very lucky ones. I did not experience any sickness or loss following the show. It matters little from whence it came, but that it did come and it is an ever-present danger in any pond or show. We are no longer blissfully unaware. Precautions have been instituted, at least, at the show level.

Have you taken the necessary precautions at home? It is not just the imported koi that can be infected with KHV (as we now know it). No koi dealer is exempt from at some time in the future purchasing a “carrier” fish without his knowledge. It is not a guarantee that your fish will be safe simply by buying “only domestics”. Let’s look at what you go through when buying a new fish, and you decide.

When purchasing a new fish, the gorgeous fish in the dealers tank with the reported history of coming from his “own stock,” born last year (or this year) and he has never had any disease, all fish in his stock are treated for any parasites and are “guaranteed clean”…

  1. Do you ask any more questions and take a really good look at the fish in the bag, maybe have the dealer take a scraping for you?
  2. Do you take the fish home, float the bag on the pond until the water temperature is the same and then release it?
  3. Do you do a salt-dip and then release it into the pond?
  4. Or do you have a quarantine tank that will house the fish for the next 4-6 weeks (or longer)?

Well, if you answered anything but “4” you lose! KHV is not readily detectible unless the fish is already dying. The fish could be a carrier and infect all your other fish. How do you know the dealer knows the health of this particular fish and where did he get this information, or how do you know you can trust him if you have a pond full of beautiful koi at stake? Most of us would really prefer to believe the dealers are the experts so we don’t have to work so hard at protecting our fish. But it is your responsibility, not theirs. If you do not have a quarantine tank, get one. There is no koi owner with a “too small” pond to forget about quarantining new fish. Now is the time to think about the consequences of adding this one more, “cute little fellow” to your friendly, loyal bunch at home…..

A quarantine tank should be the cleanest water on your property. It should be deep enough and highly filtered, covered with a net to prevent escapees from succeeding, and close to a water supply. It should be close to the house where you have easy access and can readily monitor the fish. It should be large enough to accommodate sick fish (as they will grow) and should hold more than one fish. It will need an aerator too. It will be a basic hospital tank.

In dealing with KHV, you will also want to be able to raise and manipulate the temperature in this tank. Raising the temperature to 72ºF for two weeks will either bring out the virus or prove the fish to be negative, according to recent studies.

What must be impressed on hobbyists is that this virus must be treated like HIV in humans. Use universal precautions. Treat every koi as though it is infected. Gone are the days of floating the bag on the pond and then releasing it 20-30 minutes later, to watch the new fish explore its new home. Gone are the days of seeing several owners’ fish in one tank at a koi show. Until there is a cure, and unless another disease arises, quarantine is the only way to go!

Now, the tools of quarantine regimen are as follows:

  1. Holding tank
  2. Netting or cover to prevent fish from jumping out
  3. Small bio-filter, preferably pre-colonized with nitrifying bacteria
  4. Small pump with protective screen over intake, hose and all parts that can harm fish
  5. Dedicated fish net and bowl for quarantine tank only
  6. Dechlorinator
  7. Test kits
  8. Pond salt (Non-Iodized salt)
  9. Microbe-Lift/TheraP

The 21-day quarantine regimen is as follows:

[Note: The following dosages assume a 100 gallon tank. Adjust for your tank capacity accordingly.] This program originally designed by Water’s Edge has been modified and presented anew that many fish deaths can be prevented.

  • Day 1: After thorough cleaning of tank, refill with dechlorinated water and set up filter with pre-colonized filter media. Add 6 oz. of Microbe-Lift/TheraP, mix 1.5 cup of pond salt with water from the tank, then distribute throughout the tank. Add fish. (Note: Koi do not fare well unless there are two of them together.)
  • Day 2: Repeat above.
  • Day 3: Repeat above. Use salt level test kit to check the salt levels.

Our goal is to have a 0.3% solution by Day 3.

  • Days 4, 5, & 6: Monitor with water tests.
  • Day 7: Add 2 oz. Microbe-Lift/TheraP, check water levels.
  • Day 8: Add another 1.5 cup pond salt. Salt level should now be 0.4%
  • Days 9 through 21: Dose weekly with 2 oz. TheraP
  • Examine fish daily.
  • Watch for odd behavior: flashing, rubbing listing to one side, rapid breathing, or closed gills.
  • Look for signs of bacterial/fungal infections: white or discolored spots, fuzzy growth on fins, tail or mouth, discoloration around gills.
  • Check ammonia and nitrite levels every other day. If these levels are high, or if the water becomes cloudy, perform a 30-50% water change, as needed. Refill the tank with water from your pond. (This will dilute your salt level, so add more salt. The total salt amount after Day 8 = 6 cups or 0.4%. If you perform a 30% water change, add 2 cups back. If you perform a 50% water change, add 3 cups.
  • Feed sparingly (every other day) only as much as your new fish will consume in 5-10 minutes and remove any uneaten food. Remember, they do not have stomachs.

DO NOT USE TANK WATER IN ANY OTHER PONDS!

Maintain water temperature in tank at 72ºF for two weeks to bring out KHV in the event fish have been infected.

According to Dr. Julius Tepper of the Long Island Fish Hospital, some, but not necessarily all of the following may suggest a KHV infected fish:

  • Sudden death
  • Loss of appetite
  • Rapid “gilling”
  • Lethargy and slow swimming
  • Body sores
  • Areas of “dry” skin (feels like sandpaper)
  • Other areas with excessive slime production
  • Whitish dead areas on the gills

If any of the above signs are seen, contact a fish vet to arrange for KHV testing.

Now the day comes and the fish have passed all their tests. It is time to put them in the pond. Take a fresh bucket with fresh pond water, put fish in the bucket, carry to the pond, and gently release the fish into their new home!

These are ubiquitous opportunistic bacterial invaders in every pond! At one time they were the only concern hobbyists had when buying fish, and they were the number one cause of fish death in spring and summer in the United States. They have been replaced by KHV but as they exist in every pond, we need to pay attention to what will cause an outbreak, and prevent it.

The first precaution is construction. A pond with sharp edges is an infection waiting to happen. Rocks at the edge of the pond will snag fish and create an opening in the epidermal protective slime layer, offering an invitation to any primary or secondary infection. As it is easier to prevent infection than cure it, it is recommended to check for any sharp objects that have the potential for fish to scrape themselves.

The second is the water quality. A clean pond will contain more good-guy bacteria and less of the bad guys. Parasites are the second way these bacteria will enter the endodermis of the fish. Parasites proliferate in dirty water and debris on the bottom. Filters that have not been cleaned will harbor the same parasite populations as the filth on the bottom of the pond.

And third, a healthy fish is able to resist many infections! Things which will cause stress for the fish, thus reducing their resistance, are changes in environment, dirty water, too high or too low pH, ammonia, nitrites, overcrowding, over feeding, inadequate filtration or water movement, handling of fish, poor nutrition, excessively high or low temperatures, toxins in the water, predators, etcetera.

What does Aeromonas or Pseudomonas look like? It will be seen first as a reddening of the skin which develops into an ulcer. These two bacteria strains will attack damaged tissue, killing tissue beside it as it multiplies. The ulcer will grow in size. Scales can easily be removed from the sore. Fungus and algae may attach to the dead tissue. The fish is literally being eaten away. Without treatment, the fish will die.

Treatment consists of intraperitoneal injections by a trained person, as a wrong move can also kill the fish. The sore can be swabbed with iodine or other topical medicine. The fish should remain in quarantine for the duration of treatment to reduce the stress of catching it daily. The pond should be examined for the cause of the infection, treated if parasites are found (by a scraping viewed under a microscope). The rest of the fish should be watched carefully for signs of infection. This is not contagious as once believed, however if there is something in the pond that opened this fish to infection, it will open other fish too.

By Carolyn Weise, Ecological Laboratories, Inc.

Once a fish becomes ill it is imperative to have a place to treat it without infecting the entire pond! And once a hobbyist has established a relationship with his/her fish, it will be more meaningful when someone tells them that one infected newcomer can kill every fish in the pond. Even worse, once that happens, we become believers! This is usually the point at which we all become REAL koi owners. We begin to seriously take responsibility for our charges out there in the pond and are now open to whatever is going to safeguard their welfare. The fish have by this time become members of the family.

I was able to purchase a large white circular-shaped polyvinyl tank, 5’ across and 3’ deep. Originally it was 5’ deep but couldn’t be delivered until we shaved off two feet. Initially I thought it might be going into my basement, but even at this size it wasn’t going to happen. So, I decided to bury it in the yard, near the house for convenience. That was when we uncovered the old (formerly used but now forgotten) heating oil tank. Rather than try to exhume the tank, we opted to bury the new quarantine facility half-way down. Leveled off and finished, it was 18” below the ground and 18” above. I found it to hold approximately 460 gallons when filled.

The next issue was filtration. I had a submersible pump, hoses, clamps and strainers to keep it from pureeing fish. On the other end I had a large rectangular box type filter connected with an overflow to return to the pond. This worked for several years until the hose separated from the pump.

I don’t like submersible pumps in ponds, but don’t mind putting them in the filter units, so it was decided to install two bulkheads through the polyvinyl tank, one for a new retrofit bottom drain and the other for the return. The box filter is leveled beside the tank with filter pads and springflo inside, and the pump is now housed in the back of the filter unit. Now, instead of the filter grinding up larger debris and pushing it into the filter it is pulling it in through the filtration materials and pushing clean water back to the tank. The next step is to separate the filtration media into cubicles. This box filter will become an up-flow and down-flow media box for super-clean water. There is a knife valve on the end for easy cleaning, with an attached hose to a designated spot away from the house. When the partitions are installed I may need to add more valves to purge dirty water.

My tank is efficient. It is close to the water and electric sources. It is sheltered and out of the wind and weather by being close to the house, so the temperatures remain more constant. I have the light from the house and porch in case I need to check them during the night. And I can keep watch on the fish from indoors.

I would just add one more thing, maybe two- koi don’t do well in solitary confinement. They need companion fish in order to heal. So I keep one goldfish in my quarantine tank for such purposes. That fish goes through all the treatments with the koi and comes through with shining colors. The second thing is the net over the tank. Whenever a fish is put in a strange place they try to escape! It’s just their nature. And when they jump they usually kill themselves unless you have a net to keep them in there. So, if you still think a quarantine tank is a luxury, I guess your fish aren’t a part of the family yet. And if you think you can’t afford a quarantine tank, mine cost me all of about $325 without the water. Compared to the prices of some koi, what are we talking about?

By Carolyn Weise, Ecological Laboratories, Inc.

If a pond is large enough, many species of fish can coexist peacefully, however in a small closed system such as most of our custom-built ponds today, this is not the case.

Understanding that in any body of water there are stratifications in which different life forms are comfortable will help in determining whether different species will be compatible in your pond. For instance, what particular needs will or won’t be met in the limited space allotted?

Comets have a wide range of acceptable parameters, such as pH, temperatures, and even water quality. They need a minimal amount of space and increase in numbers rapidly. Shubunkin and other fancy carp are very comfortable in a goldfish pond with comets. The lionhead and other very special goldfish varieties are best viewed in a tank, so they are not particularly suited to pond life. Their lack of swimming capability would make them easy targets for predators.

Orfes on the other hand need room to run, being fast swimmers and school fish that grow to about 18” at maturity. They prey on slower invertebrates, fish fry and insects. They are not aggressive with other fish in the pond and will not “nip” other inhabitants.

Somewhere in the middle are Koi. Koi are large-growing, high demand fish that need attention to water quality, pH, ammonia, nitrites, nitrates, phosphates, and are sensitive to overcrowding. They are sensitive to parasites and bacteria to which comets are practically immune. They will benefit from doses of salt in the pond for the occasional parasite attacks, but Orfes can die from salt in their water.

What does this mean? I conclude that koi and comets have very different requirements in their living space, so they would do best in their own ponds. Granted, the comets wouldn’t mind living in a koi pond, but the koi won’t do so well in a crowded goldfish pond. Just as the koi will destroy the goldfish pond that contains lovely plants…. And Orfes can coexist with koi if care is taken in medicating the pond and there is sufficient space for all. In fact, they are fun to watch as they dart around in a school of 5-6, not caring what the koi are doing. They are not happy if there is only one.

What about catfish? Many people want to put catfish in their koi ponds, so there are some things to be considered here too. Catfish grow to huge sizes—rapidly! They will eat smaller fish and they do not need clean, clear water. In fact, they prefer the comfort of murky waters where they navigate wonderfully with the sensory guide of their barbells (sense of smell) and hearing. The consensus is that these fish will clean up the uneaten food that settles to the bottom, being the bottom feeders they are, but we fail to realize that anything that eats also poops! It is still in the pond, in one form or another. So you don’t really want to put catfish in with small comets, do you? And given the different water quality preference, you wouldn’t want to pair it up with koi either. I would think of putting catfish together with something like bass, trout and sunnies, if you have the room.

Hobbyists in the southern US have put algae eaters (tropical fish- mainly Plecos) in their ponds and some have written to us about whether these fish are really compatible with their other pond fish. Again, look at the individual needs of each fish. It isn’t whether or not they will fight. It is whether or not they will survive under the same conditions. The plecostomus has a huge sucking mouth, but a very tiny throat, so it isn’t eating any other pond fish. It is an herbivore. If any fish are dying, more than likely their personal needs aren’t being met. Would a larger pond meet them? Perhaps it would, especially if there were enough room for stratifications, different areas with different pH and temperature zones with a variety of food sources accumulating in these “pockets” of life.

Turtles in a pond may be asking for trouble. Pet turtles, water turtles such as Red-eared Sliders which are native to ponds across the country, are fish eaters. They are good swimmers and difficult to recapture once living in a pond. So, before putting your pet turtle into a fish pond, know you may be feeding him your fish.

Frogs are another natural pond inhabitant that we love to see at the pond’s edge. They are the best bug-eaters and evening serenaders! People buy tadpoles and add them to the pond so the frogs will stay around. We worry about how to help them over winter. We love them. But are they really good for our pond? Some of the negative aspects of frog ownership are the bacteria that frogs bring to a pond, the bullfrog’s capacity to eat small fish, and perhaps the neighbors’ complaints if they don’t like the serenading as much as we do.

By Carolyn Weise, Ecological Laboratories, Inc.

When going to koi shows the natural human reaction is to buy koi. Why not? After all, there is such a wonderful selection of beautiful fish that should be swimming in your own pond, and the prices are right! So, you shop and buy, and the dealer will pack the fish in plastic bags filled with pure oxygen, tied up with a rubber band. Now, when you arrive home, what do you do? According to most koi hobby lore, we have been adding pond water to the bags in way of acclimating the fish to your own pond water chemistry…. THAT’S THE BAD NEWS….

Here’s what NOT to do:

Never add pond water to the bag! Simply by opening the bag, some of the carbon dioxide will be released into the air and the loss will result in an instant increase in pH inside the bag. As the pH rises, so does the lethality of ammonia in the water.

According to Norm Meck, the Water Quality expert for the AKCA’s KHA program, when a fish is contained inside the double-wrapped plastic bag for any length of time its own exhaled carbon dioxide will actually combine with the water producing carbonic acid to lower the pH in the bag. The ammonia being produced by the fish’s respiration will then result in a harmless ammonium product! THAT’S THE GOOD NEWS.

When the new (pond) water is added, the pH is immediately raised, by the pH in the pond water! The first thing happening to the fish is STRESS. Ammonia burns the gills, much like chlorine, and it takes up to eight months for it to manifest in a fish death, long after you have forgotten about acclimating this fish to the pond water…. Besides, that’s what you were told to do, right? Sometimes we are given the wrong information unintentionally.

Here’s what TO DO:

So, it is fine to float the UNOPENED bag on the pond (or quarantine tank) for up to 30 minutes to adjust the water temperature, and then, without adding any pond water, lift the fish out of the bag and directly into the clean water. Throw away the water from the bag. Never put any of it in the pond. Your fish will thank you…. Eight months from now!

By Carolyn Weise, Ecological Laboratories, Inc.

There are different schools of thought, and several ways of defining how many fish can fit into your pond safely. Taking into consideration that a healthy fish, especially koi, will grow each year, your last year’s figures will be wrong by now. Eventually, Mother Nature will thin out an overcrowded pond! In order to prevent loss of your favorite fish, we have a couple of easy ways to figure out how many fish you can expect to SAFELY keep in your pond.

Figuring in the vast differences in filtration units and gph pumps on the market, you may again be tempted to put one or two more fish into the pond than is necessary, but when the power fails, you will find out if that was really SAFE.

Now, if you are not a person who wants to take time fiddling around with filters, water test kits, and the rest, please use your own discretion and put less fish in the pond. If on the other hand you are always doing something with the pond and love being a part of the daily maintenance, you will perhaps be able to stock more fish. Good water quality and thorough pond maintenance are key to koi survival rates.

According to Mid-Atlantic Koi Club’s book, “From the Pages of MAKC News”, the number of 12” equivalents is as follows:

6 inch koi 0.1

8 inch koi 0.3

10 inch koi 0.5

12 inch koi 1

14-16 inch koi 2

18-20 inch koi 5

24-28 inch koi 12

Thus, one 12 inch koi equals ten 6 inch koi and one 14 inch koi equals 125 3 inch koi in loading the pond. Doubling the length of the fish causes roughly a ten-fold increase in the pollution rate. This is why a properly stocked pond can become vastly overcrowded in just a year or two as the fish grow to a larger size.

Overcrowding reduces oxygen levels, increases the number of bacteria and parasites, causes greater variation in feeding… and causes release of pheromones—one of them suppresses the immune system of weaker fish—another suppresses reproductive functions.

Be aware of compound stress effects. Several small factors can combine to produce really bad results…….”

That tells us why we don’t want to overcrowd the pond, now we need to know how to go about not over stocking in the first place, right?

First, you need to know exactly how many gallons are in your pond system. Then take into consideration what type of fish you are putting in the pond. If you want koi, they grow quickly and size is not necessarily contained by the size of the container.

Here are some suggestions for stocking, per size of koi and how much water it requires:

One 8” koi requires 50 gallons

One 16” koi, equivalent to four 8” koi, requires 200 gallons

One 24” koi, equivalent to twelve 8” koi, requires 600 gallons

HELPFUL HINT: Standard koi are measured from the tip of the nose to the end of the tail. Butterfly koi are measured from the tip of the nose to the start of the tail, not the end of the tail, when measuring the fish.

Another way of looking at STOCKING LEVELS:

No more than one 12” koi per 10 square feet of pond surface area ( which assumes good biological filter and good aeration).

Carolyn Asks: Do you know how big your pond is? Now do you know how many koi you can keep in the pond? An overcrowded pond looks like Manhattan during rush hour. Not a pretty sight. A well-stocked pond is a lovely picture and a picture of health!

By Carolyn Weise

Salt is used as a parasite prevention and treatment, primarily spring and fall, or if symptoms are noticed during the summer months. Symptoms include flashing, jumping, gasping for air, reddened fins, lesions, erratic swimming, fungal-looking infections, malnutrition, excessive slime coat, and fish deaths.

The recommended dosage for salt is 0.3%. At this solution most emerging parasites will be killed. However, many plants in the pond will also suffer and die at this salt level, so it is advisable to remove all plants, wherever possible, before adding salt to the pond. In ponds where it is not possible to remove the plants or to lower the water below the level of the plants for the duration of treatment, it is recommended the salt level not exceed 0.1%. (At 0.3% this would be 2.5 lbs. of non-iodized salt per hundred gallons of water.) It should be administered in small, dissolved increments until reaching the 0.3% level, over a 3 day period. A salinometer is a very handy instrument when using salt.

For free-swimming and external parasites, 2-3 days would be sufficient to kill most populations. For parasites such as ICH, which is a ciliated protozoan that encysts under the epidermis of the fish and cannot be eliminated until free-swimming, the time frame for salt use must be extended to allow the life-cycle to process over 5+ week period, depending upon the water temperature. (It is roughly 2-5 days in warmer temperatures but can be up to and beyond 5 weeks in cold temperatures.)

One of the benefits of salt is that it is one of the safest treatments for the hobbyist to use and least harmful to bacteria in the filter.

NOTE: Salt is a chemical and overdose is possible if not used with care. These are fresh water fish, not salt water or brackish-water fish, so salt should be used in moderation. To use salt all year will serve to promote salt resistant parasites.

NOTE: Also, when using salt in the pond, it is important to have a way of removing the salt from the pond. It can’t be discharged onto the garden, so a purge line directly to the sewer or other appropriate receptacle should be planned beforehand.

a.. Salt is used to increase the slime coat at times of stress.

b.. Salt will regulate osmotic balance to reduce stress.

c.. NEVER USE IODIZED SALT. Always use Non-Iodized table salt, Kosher Salt, Water Softener Salt, or Sea Salt in the pond.

By Carolyn Weise

Sexing fish is difficult to impossible until they are mature enough to spawn. With koi, the females will develop a larger, wider body, capable of producing thousands of ova (eggs). The males will remain slender, long-bodied fish. Unlike birds or other wildlife, the color or eventual size will not distinguish male from female in koi. Both are capable of the same beautiful colorations. Unlike dogs, or cats, there is no personality difference either. Unlike other fish, koi do not remain small given a small container in which to live. They grow to their genetic predisposition, up to 36” in length. Koi are oviparous, or egg laying fish. Unlike breeding purebred rottweilers or collies, the parent fish do not necessarily bring forth young that look like them. Some will revert back to the original black/brown colored Magoi which used to inhabit the Japanese rice paddies. Others may show color combinations that are unique and wonderfully unexpected.

The only way to control breeding is to isolate two parent fish and remove them once they have spawned. Once spawning takes place the parents will consume many of the eggs. Likewise, the only way to prevent unwanted spawning is to keep only same sex fish together in the pond.

In spring, you will see the first signs of which sex is which. The females that have reached maturity (around 3 years of age, however they can and have bred at 2 years), will begin to swell with eggs. As the water temperature warms, the males will also begin to actively chase the females. Generally when the water reaches the 72ºF point, and especially if there are plants in the pond, the chase begins in earnest.

The males will push the females against rocks, plants, and the sides of the pond to squeeze out the eggs as they release their milt to fertilize them. Injuries and deaths have occurred from spawning due to crowded ponds or too many males. What is obvious to the pond owner (in the morning) is froth on the top of the pond and a strong fish smell. That is the excess of protein from the spawn during the night. As a rule, the spawn will continue throughout the day, for up to two weeks. Or it can end after a couple of days and begin anew the week after.

After the eggs are released and fertilized, the will attach to the rocks, plants or liner of the pond. In 3-4 days they fry will hatch. Any eggs that turn white will have been killed by fungus. The fry that hatches becomes free swimming after hatching. Within one week colors can be seen, although the fish will change colors as it develops for the first 2-3 years of its life. The parent and larger koi will no longer try to eat the babies once they are able to identify them as fish. They are not cannibalistic.

Nor are they protective parents. These fry are on their own from the moment of their birth. They will face predatory insects, birds, frogs, and illness. Yet, many will survive. It is difficult to realize that each of these tiny beings may grow to 36” and may need a new home…. Please consider this when you decide to breed your fish.

Other methods of spawning are artificial, such as squeezing the eggs and milt out of two parent koi, into a container for fertilization, then adding them to an incubation tank to develop. Koi breeders (farmers) have a succession of ponds to “grow out” these babies, and cull those that aren’t worth keeping. They keep only the best of the best.

Beside plants and natural pond environments, hobbyists have used breeding mats, clean mops and brushes as receptacles for eggs during spawn to collect the eggs for sale later on. Many a koi dealer has started out in just this way!

Koi have equally as many enemies as they have admirers. Depending on what part of the world you live, these fish will have to face natural predators. Given the mature size these fish can easily be seen from the air, or with the flashy colors will be noticed from a distance. Add a waterfall and the sound will send the signal “fish dinner over here!”

There is no “one” way to safeguard the pond from all types of predatory pests. Some of these pests are also protected by law! Herons, for instance, are protected by international migratory bird laws. Ospreys are protected in New York. And so on. What is one to do? The answer to predation by birds is in the construction of the pond and by using clear monofilament fish line to deter attack.

I have used the monofilament line by stretching it back and forth across the pond, at different heights to make it more difficult for long-legged birds to maneuver, from 3’ beyond the water’s edge. In general, all that needs to be done is to make it easier for the bird to go elsewhere to find its next meal. They have excellent memories, some say “photographic” and can see ponds from the air, so will find their way back to your pond each year in their migratory flight. Since using the monofilament line I haven’t had to fight with the herons or egrets since!

Small predatory birds, such as kingfishers, will take more of a close-knit netting to surround the pond which may not be as attractive as the others, but this is an individual choice- koi or net? They are excellent fishing birds and can puncture what they can’t carry.

The next on the list of common pests would be the ubiquitous United States raccoon! This masked marauder is found everywhere and loves fish for dinner. A good sized koi can feed the whole raccoon family. When we build our ponds with sloping sides and bog areas in the pond in which the fish can swim, we are actually setting up “feeding stations” for raccoons, cats, wolves, bears, and other 4-legged fish-munchers. In this case, by constructing the pond with straight sides and planting or building next to the pond so they can’t get good footing at the pond, the fish have better protection. If all that fails, forget about motion-detecting sprayers. Get serious and install low-voltage electric fencing! It is reasonably priced and easy to install. Only turn it on when needed, like at night. These animals also have good memories. They say once a raccoon fishes in your pond you can never safely keep fish again. They will always return. But not if you can convince them it isn’t where they want to go. Give them something to remember other than the fish. Make it too expensive a meal!

I would never recommend shooting any predator that is fishing in my pond. I would probably have to repair the liner after I shot holes in it, even if the water didn’t deflect the bullets into my neighbor’s house or barn.

There is very little that can be done about predatory snakes if they are in your area. Other problems to watch for are otters, opossum, lizards, and whatever, but if they are native to your area, talk to others and find out what works for them. Trap the perpetrators, remove them, and pay to have someone else do it for you, or enclose your pond so nothing can reasonably enter. Bottom line is that we are building natural-looking environments and nature will come to call sooner or later. Build the pond deep, the walls high, and the covers strong!

BEWARE of invasive species of plants! When planning your landscape around and in the pond, always picture the mature plant, the amount of space required, and if you want it to look natural and healthy, pick species that are native to your area.

I have a lush garden, planted for all seasons living in the northeast, because I chose plants that are hardy HERE. They like the soil HERE, the sun and temperatures HERE, and the drought HERE. If you want ease of maintenance, choose plants compatible with your area. Always look at the recommended zones on labels when buying plants. I also prefer to shop locally rather than mail order because I feel fairly certain these plants are more suited to my needs.

In my pond, I do the same. My pond is a koi pond, but not in the traditional sense as it contains plant pockets I like to call “bogs”. Each is planted with only one or at most two specie of plant. I tried for years to grow a certain lotus or lily only to be disappointed when nothing happened, or worse, it died altogether, the subsequent year. Then I realized there are amazing types that will bloom and flourish in my pond with very little care. It is these varieties that have given me such a good name. All I did was to give up trying to be the best, and suddenly, I got better! Of course, although this is sound advice, it is only my own opinion….

I would recommend the typha minima (miniature cattail) rather than the tall cattail for anyone wanting a natural look without the mess and bother. It is not invasive like its taller cousin. I want a water garden, not a swamp. If a plant is marked, “can be invasive” or “spreads easily” it is not a good choice for small gardens. Maybe it is not a good choice for the large garden either unless that is the predominant plant desired. Something that is a “good groundcover” will spread with abandon, so you should consider rampant growth pattern when choosing its neighbors because they will be outgrown quickly.

Ask at your local nursery and ask friends to share plants from their gardens. Once the pond plants get established, the koi don’t seem to bother with them anymore. So, plants and koi CAN coexist after all!

NOTE: MICROBE-LIFT/Ensure and Bloom & Grow are specially formulated to assure the plants in your pond have the ability to utilize nutrients from the pond water. They should not need additional fertilization. Healthy, vigorous plants can withstand infestation better than you’d think!

By Carolyn Weise, Ecological Laboratories, Inc.

If a pond is large enough, many species of fish can coexist peacefully, however in a small closed system such as most of our custom-built ponds today, this is not the case.

Understanding that in any body of water there are stratifications in which different life forms are comfortable will help in determining whether different species will be compatible in your pond. For instance, what particular needs will or won’t be met in the limited space allotted?

Comets have a wide range of acceptable parameters, such as pH, temperatures, and even water quality. They need a minimal amount of space and increase in numbers rapidly. Shubunkin and other fancy carp are very comfortable in a goldfish pond with comets. The Lionhead and other very special goldfish varieties are best viewed in a tank and may need frequent treatment for fungal infections in their wens, so they are not particularly suited to pond life. Their lack of swimming ability would make them easy targets for predators.

Orfes on the other hand need room to run, being fast swimmers and school fish that grow to about 18” at maturity. They prey on slower invertebrates, fish fry and insects. They are not aggressive with other fish in the pond and will not “nip” other inhabitants.

Somewhere in the middle are Koi. Koi are large-growing, high demand fish that need attention to water quality, KH, ammonia, nitrites, nitrates, phosphates, and are sensitive to overcrowding. They are sensitive to parasites and bacteria to which comets are practically immune. They will benefit from doses of salt in the pond for the occasional parasite attacks, but Orfes can die from salt in their water.

What does this mean? I conclude that koi and comets have very different requirements in their living space, so they would do best in their own ponds. Granted, the comets wouldn’t mind living in a koi pond, but the koi won’t do so well in a crowded goldfish pond. Just as the koi will destroy the goldfish pond that contains lovely plants…. And Orfes can coexist with koi if care is taken in medicating the pond and there is sufficient space for all. In fact, they are fun to watch as they dart around in a school of 5-6, not caring what the koi are doing. They are not happy if there is only one.

What about catfish? Many people want to put catfish in their koi ponds, so there are some things to be considered here too. Catfish grow to huge sizes—rapidly! They will eat smaller fish and they do not need clean, clear water. In fact, they prefer the comfort of murky waters where they navigate wonderfully with the sensory guide of their barbells (sense of smell) and hearing. The consensus is that these fish will clean up the uneaten food that settles to the bottom, being the bottom feeders they are, but we fail to realize that anything that eats also poops! It is still in the pond, in one form or another. So you don’t really want to put catfish in with small comets, do you? And given the different water quality preference, you wouldn’t want to pair it up with koi either. I would think of putting catfish together with something like bass, trout and sunnies, if you have the room.

Hobbyists in the southern US have put algae eaters (tropical fish- mainly Plecos) in their ponds and some have written to us about whether these fish are really compatible with their other pond fish. Again, look at the individual needs of each fish. It isn’t whether or not they will fight. It is whether or not they will survive under the same conditions. The plecosomus has a huge sucking mouth, but a very tiny throat, so it isn’t eating any other pond fish. It is an herbivore. If any fish are dying, more than likely their personal needs aren’t being met. Would a larger pond meet them? Perhaps it would, especially if there were enough room for stratifications, different areas with different pH and temperature zones with a variety of food sources accumulating in these “pockets” of life.

Turtles in a pond may be asking for trouble. Pet turtles, water turtles such as Red-eared Sliders which are native to ponds across the country, are fish eaters. They are good swimmers and difficult to recapture once living in a pond. So, before putting your pet turtle into a fish pond, know you may be feeding him your fish.

Frogs are another natural pond inhabitant that we love to see at the pond’s edge. They are the best bug-eaters and evening serenaders! People buy tadpoles and add them to the pond so the frogs will stay around. We worry about how to help them over winter. We love them. But are they really good for our pond? Some of the negative aspects of frog ownership are the bacteria that frogs bring to a pond, the bullfrog’s capacity to eat small fish, and perhaps the neighbors’ complaints if they don’t like the serenading as much as we do.

One last favorite of the hobbyist is the Japanese Trapdoor Snail.  While this snail is not harmful to your pond, it probably isn’t the answer to your algae problem either.  But other snails can be a nightmare if they come in on plants.  They will eat plants, proliferate and even clog pumps.  Yes, they can be a veritable nightmare.

By Carolyn Weise

The benefits of a waterfall are many, as are streams, however they are generally chosen for aesthetic purposes. The sound of running water, the natural feel of water running through the garden, and the reflection of birds, sunlight and flowers have a relaxing effect on our blood pressure and other senses. What is not as well known is the benefit to the pond. The moving water actually gathers oxygen as it travels over rocks and splashes into the pond. Of the waterfall and stream, the stream is probably the more efficient oxygenators of the two. But the waterfall remains the more popular. Let’s first look at construction of a waterfall.

WATERFALLS: When building a waterfall, it is helpful to consider water direction and flow into the pond, as it is to be a big part of the circulatory process. A healthy pond does not have ”standing” water, but is continually moving every part toward the drain and filters to be cleaned and refreshed. Therefore, the angle you choose and the placement should be farthest from the skimmer and filter intake unit (bottom drain). The height of the waterfall will depend upon the size and surface area of the pond. A tall heavily splashing waterfall will empty a small pond quickly, therefore too much splashing should be avoided. By proportioning the falls to the pond you will have a better system and fewer problems. Almost all pond leaks can be traced back to improperly constructed waterfalls.

A reservoir at the top and bottom of the waterfall will not only help contain the water, it will also offer a place for more rocks as an aid in oxygenation. Plants can be added to the top of the falls. The first step after determining the site for the waterfall is to build a foundation, for which cinder block or concrete blocks work well. This will be set in place, mortared to smooth out any rough edges, and lined with EPDM liner. It can then be ½ filled with sand and smooth stones, leaving a shallow pool for gathering water. There is nothing pretty or natural about water spurting out of a PVC pipe. All liner and pipe work should be covered by rocks, and the liner must be higher than the water level to prevent future leakage.

When adding a waterfall to an existing pond, it is best to overlap the liner into the pond rather than to try tucking them together. The water will “wick” out between the two pieces of liner if they are together. It is also very difficult to glue two pieces of liner, especially if one is already used, without leaks. Arrange the waterfall rocks so they overhang the pond for a more natural look and match the waterfall rocks to the ones used in constructing the pond.

Tip: Use a variety of rock sizes, rather than uniform size, as it will look natural if there are, for example, large boulders and very small rocks together.

STREAMS: Streams are incredibly useful as bog systems, vegetable filters, oxygenators, and are attractive to wildlife. A woodland-type stream can be made with EPDM liner and muscle power.

Bring in dirt, or dig and move, to build up an area, 15-30’ long and 5-6’ wide. Use stones to support the dirt along the sides and hollow out individual pools in the stream bed. Each pool should be 3’ deep and 4-5’ wide. Leave partitions of dirt between them, and have each one lower than the one before, going down toward the pond. Start at around 4’ high for the first one. The partitions between each pool will be spillways from one into the next.

Then stretch a liner over the entire stream, leaving 2’ on each side, the top and bottom. Mold it into each pool carefully, and ½ fill with sand and a layer of smooth stones. Place a flat rock on the spillway, at the waterline for each pool. This will assure a good flow. Be sure to use a level and have the sides higher than the spillway, or the water won’t go where you planned. The sides should be 3-4” above the spillway and waterline levels to prevent water loss.

Then tuck in the liner, in and under rocks along the side of the stream. The water line will enter from the top of the first pool, and should be hidden by rocks. It must be secured so the water cannot go anywhere but into the first pool. Bury the line back to the filter or pump.

Plants along the stream will add to the natural look and those used in the stream will become vegetable filtration for the pond!

Tip: Install knife valves for winterizing, or diverter to underwater return, so the stream and waterfall can be shut off and prevent super-cooling the pond when temperatures drop below 50ºF.

by Tom Burton

If the bottom of the pond has been sloped a bit to the bottom drains, most of the sediment will make its way from the pond to the filtration system without any help from the koi keeper. The returns through the sides of the pond from the filtration system will produce a bit of a current and keep particulate suspended and headed for the bottom drains or skimmer. However, there are routine maintenance tasks that need to be carried out periodically.

  • Purging of the settling chamber. Heavy material will settle to the bottom over time (the amount depends upon the fish load and many other factors) and will need to be drained to waste. This is accomplished by turning off the pump, closing the knife valve in the drain line to stop the water from entering from the pond, then opening the chamber purge line knife valve and letting the chamber empty. Then reverse the procedure to get back up and running.
  • Cleaning the material used in the mechanical filter. This is where lighter material that didn’t settle in the first chamber is stopped – “filtered” – from the water. There is a variety of materials used to accomplish this but no matter which is chosen, it must be cleaned from time to time. The use of a powerful stream from a garden hose works well and since we’re not asking this material to work as a surface for the “good guy” bacteria to live on, we don’t need to be concerned about the chlorine killing them off.
  • Cleaning of the catch-basket in the skimmer. The dust, pollen, leaves, etc. that end up here, need to be gotten rid of as needed so the water flow is unimpeded.
  • Cleaning of the media in the biological processing station. The water going to this part of the system should be as clean and free of particulate matter as possible so that the cleaning of it is necessary only rarely. We don’t want to destroy or reduce the numbers of “good guy” bacteria that take up the ammonia and nitrite for us. So, this cleaning can safely be done in pond water or a small portion taken at a time and hosed off, then another portion at a later date, etc., until the job is finished.

(Carolyn says: We have Nite-Out II and PL Gel to recharge filter media after cleaning.)

  • Water testing. At a bare minimum, tests for ammonia, nitrite, and KH should be done frequently (weekly for the first several months then maybe less frequently but routinely and among the first things if there appears to be a problem). Ammonia and nitrite readings should always be zero and KH should remain above 80 ppm.

(Carolyn says: Did you know that the nitrifying bacteria use 7.1 ppm KH to convert 1 ppm ammonia to nitrate?)

  • Water changes. Routine changes of 25% per week in the summer and 10% in the winter are recommended. The primary reason is to replenish the mineral content in the water -vital to fish health. Also, it is the first line of defense if there appears to be a problem – even up to 50% when toxins such as chemicals from lawn or tree and shrub treatments are suspected. Just be sure and neutralize the chlorine or Chloramine.

(Carolyn says: MICROBE-LIFT has Super Dechlorinator+ and Aqua Xtreme to remove toxins and keep your fish safe!)

by Tom Burton

The next step is to lay out the pond perimeter using powdered lime or a rope or hose to see what this thing is really going to look like in the spot you’ve chosen. Again, it’s probably good to leave this for a couple of days to see if that’s what you really had envisioned. Then, start digging.

If you live in an area where ice might be a problem, slope the sides about 20 degrees so the ice can slide up as it expands instead of straight out (and through your liner). Dig out the trench for the 4″ bottom drain pipe and run it all the way to where the rest of the filter system will go. If a straight shot is not possible, use 45-degree elbows to raise or turn the pipe rather than 90’s. The fewer bends the better. Put the bottom drain and all the pipework in place to check all the measurements before gluing. It’s a good idea to cover the whole top of the drain to keep dirt out. If the drain is sitting on firm virgin clay/soil, there’s no need to set it in concrete. The weight of the pond water will hold it steady.

Returns from the pump and filtration system to the pond are usually via a waterfall and a couple of through-the- liner bulkhead fittings that allow for the creation of a current by using directional “eyeball” (spa) fittings or 90 degree Fernco elbows with the clamps removed (so the fish don’t hurt themselves) and glued to the pipe out of the bulkhead. Don’t be afraid of the through-the-liner returns. Just be sure to tamp the backfill around each pipe so they’re in a solid setting. It usually takes two people to install them and only go arm’s length down the side – one person holds the outside of the fitting outside the pond (male threaded) while the other tightens the nut that sandwiches the liner against the flange (female threaded) for a water-tight installation. A bit of aquarium-safe adhesive wouldn’t hurt either.

Tip: Inch-and-a-half PVC, schedule 40, is good for most water transfer functions. However, if the run is longer than about 15 feet, 2″ works better by reducing flow resistance. If flexible PVC is used, be sure to use the PVC cement made for it. Also, always use PVC cleaner before gluing (a clear one is available if you don’t want to see all the typical blue around joints).

Tip: Fernco couplings make pipe joints simple. This is a rubber coupling with stainless steel clamps and comes in many configurations and is available at home centers and plumbing supply houses. After installation, check for tightness periodically if used near pumps. They have been known to loosen, detach and allow depletion of an entire pond.

Tip: Skimmers are a really “nice-to-have.” Either the inexpensive (about $40) aftermarket one or a swimming pool type that installs in the liner just like it does in a liner swimming pool. They keep the surface looking great and both require a pump to operate (external is best – 2,000 to 2,400 GPH).

You’ve already decided whether you’re going to have a partially raised pond and what that structure will be made of and look like, or you know what type of stone you’re going to use around the place. The rule here is to hide the liner and the plumbing. The water level should always be a little above the exposed liner inside the pond. This means that the liner must not only go under rocks placed around the edge of the pond, it must come up behind them as well. To accomplish this, a shelf an inch or two below the intended water line is in order (remember, you know where the water line is going to be because of the levels shot with the transit). Hiding that back edge or tip of liner can be accomplished by using overlapping rocks, plants, decking, you name it (see diagram). Here’s where your imagination comes to play. Just don’t let it show either inside the pond or out. Decide how the excavation at the top perimeter of the pond should be done to arrive at the look you intended. It’s a good idea to steer clear of a necklace or swimming pool look except maybe for a partially raised pond.

Tip: The edge of the pond should be slightly higher than grade so that rainwater doesn’t flow into the pond.

Now’s the time to check the dimensions of the pond again and calculate the size liner you’re going to need. Length plus 4′ plus (depth x 2), and width plus 4′ plus (depth x 2). That 4′ in each direction is to give you 2′ overhang all around. Thus a pond 25’ x 13’ and 3′ deep needs a piece of liner a minimum of 35’ x 23’ plus any for bog garden, streams or waterfalls. If the stones you’re using are more than 18″ wide, you will need to add liner accordingly. The rule of thumb is, if water is going to be there, there must be a covering of liner AND a lip at the back to contain it. Don’t forget to include a planned stream or waterfall. They need to be lined as well and the water contained on the sides (with the liner hidden of course). One contiguous piece for everything, to include the water garden if that’s in the plan, makes it a lot easier but there is an EPDM bonding material that does well when applied properly. Or, there is an EPDM tape that will work if applied with care and correctly. There are some good diagrams and examples of perimeter treatment in the Tetra Encyclopedia of Koi and though this book is an excellent reference, it’s rather dated, particularly in filtration, so check with other folks before accepting the material as gospel. The fundamentals are all there but technology and new developments have passed it by.

Now the hole is perfect and it’s time to lay padding for the EPDM. Old carpet works well, as does sand or carpet padding, almost anything that will give a bit of cushion and help the liner resist puncture from underneath. Once that’s in place you’re ready to lay the liner. And since its pretty heavy, fellow club members or friends are needed for this operation. One method is to lay the whole liner out and roll it up from the sides to the center lengthwise then tie it in a few places to facilitate carrying by you and your friends. Then march single file through the hole, placing the liner properly lengthwise, and then roll it out from the center and up the sides. Another way is to get six people to hold it out over the hole then gradually let it drop into place. Once it’s in the proper position, smooth out the bottom over the hole for the bottom drain, mark the hole with a Magic Marker, then cut the hole in the liner as neatly as possible with a utility knife. Then apply a fish friendly (aquarium safe) adhesive/caulk between the liner and the bottom drain, then on the collar that will sandwich the liner and the bottom drain together. With the collar in place install the screws or whatever fasteners came with the drain trying to apply equal tightening all around. Wait for that to set-up according to the directions for the adhesive, then proceed to lay the liner so as to avoid as many folds and wrinkles as possible (this the major down side to using a liner – some folds and wrinkles can’t be avoided and will harbor crud). This was my saddest day as I couldn’t imagine getting that huge sheet of rubber to flatten out and look like anything – but of course it mainly did and with gorgeous fish swimming around I don’t notice it anyway. As the pond slowly fills it’s possible to work even more wrinkles out as the weight of the water starts to work in your favor. It’s not a good idea though, to stretch the wrinkles out by letting water act as air would in a balloon – this ends up thinning the liner. Some folks have filled their pond, left it sit for a few days, then pumped it out and started the wrinkle removing process again as they refilled. They say it helped. Also, the use of 6″ EPDM tape can help flatten and seal major folds. The anti-vortex domed top for the drain should be set about 1 ½” off the bottom.

Tip: When filling the pond, water should be metered so you will know FOR SURE how much is in there AND in the entire filter system together. You’ll need this info if/when you must treat for parasites or other baddies as dosages are based on water volume (and no one I ever heard of has gotten away without some).

Tip: DO NOT CUT excess liner until you are SURE it isn’t needed. This is a lesson learned the hard way by too many of us.

Now to the filtration system: At this stage you should have the system all hooked up and in place or have all the necessary parts on hand. You’ve kept the water in the pond from running out the drainpipes by closing the knife valve for each. Look at the attached filter diagram as only one of many ways and means to arrive at the same end; good water quality. The filter system is the key to that and if we don’t have good water quality, we can’t keep koi (very long) – period. The system incorporates bottom drain to settling chamber to mechanical filtration to biological processing to pump to pond. It doesn’t matter what the containers look like, or what their shape is as long as they hold water and don’t lose their shape when filled. The settling chamber won’t work if we feed it too fast. The mechanical filter won’t work if all the water isn’t forced to travel through the filtration media. Likewise, the biological processing station won’t work if the water can go around the media you’ve selected as the home of the good guy bacteria. Water will seek the least line of resistance and all of your efforts will be for naught if it doesn’t go THROUGH the media. Also, match the media to the type container. Brushes do well in round, or straight-sided square or rectangular containers. Ribbon type media goes in either as well. Ribbon material will try to sneak out purge drainpipes if you don’t contain it (say in nylon drawstring laundry bags or by having a grate at the bottom of the container). However, these are just a few of the potentials for media so ask and look around. They are ones I’ve used successfully though.

Now we can start up the pump and test our recirculating, gravity fed system. The pump should obviously be outside the pond and move 2,000 to 2,400 GPH. It normally doesn’t have to create much head or pressure as waterfalls should neither look nor sound like Niagara Falls. The effect should be soothing, not kinetic or frantic but that’s a personal thing I guess. Most of the water being pumped will go to the through-the-liner returns to create the current we mentioned earlier. The fish love it and the crud is moved to the bottom drain where it belongs. There are several choices of pumps and any one that uses around 3 amps and is quiet will do just fine. Most have 1 ½ ” input and output connections. If you’re going to use 2″ pipe from (and/or to) the pump, just use a 1 ½ ” to 2″ coupling. Installing a ball valve (Teflon ones are best) on the output side of the pump for complete control, and a flow meter that displays 20 to 80 GPM, are highly recommended.

Tip: Amps x voltage = watts x 24 hours divided by 1000 = kilowatt hours (KWH). Example: 3 amps x 120 volts = 360 watts x 24 hours = 8640 watts divided by 1000 = 8.64 kWh x rate charged by the electric company per kWh (mine is 15 cents) = $1.29 per day to operate the pump (or $38.88 per month).

Tip: Union couplings on the input and output side of pumps make for quick disconnects.

You’re up and running now and have used some type of dechlorinator to neutralize the chlorine in the water and are ready to add a few fish that will provide the food (ammonia) for the good guy bacteria to get started. Remember that our biological processing station is only RE-active and never PRO-active so it always has to catch up to any increased bio load (so we never want to add a lot of fish all at once).

Tip: Call your water company and ask if they use Chloramine to get rid of bacteria. If they do, you need a neutralizer that attacks that specifically. Just read the label on the product.

(Carolyn says: MICROBE-LIFT Aqua Xtreme neutralizes both chlorine and Chloramine.)

(Carolyn says: Establishment of bacterial filters used to take up to six weeks each season, but not anymore. MICROBE-LIFT/PL Gel Filter Pad Inoculant and ML/Nite-Out II will start up a filter quickly, as does ML/Super Start for Bubble Bead Filters.)

Tip: An ultra-violet sterilizer is the best way to get rid of single celled Planktonic algae (which makes our water green). The wattage needed depends upon a lot of things, such as nitrate in the water and hours of sunlight on the pond (algae is a plant and needs food and sunlight to thrive). A 40-watt UV with water flowing through it at 900 GPH, works very well for most ponds (4000 to 6000 gallons). If you need more power and water is run through two 40-watters one after the other in sequence, you can increase the flow to 1800 GPH (or 3 to 2700 GPH, etc.) Those are figures I know to work but the hobby has more art to it than science so a little deviation either way probably wouldn’t matter. A branch off of one of the returns or even placed in a return line, can supply the water but you’ll need to know what the flow rate is. Installing a flow meter in the line will take care of that and the ball valve on the line after the pump will be your control. The alternative is a separate small submersible pump (of the type without oil in it) picking up water from the processing station or the mechanical filter and pumping to the waterfall or even from one container or section to the other, will work.

The Importance of Carbonate Hardness (KH) in your pond

The Importance of Carbonate Hardness (KH) in your KOI Pond

The most overlooked, yet most important water parameter of your KOI Pond is KH.  KH is the measure of the Carbonate Hardness in your Pond.  Carbonate Hardness is simply the amount of Calcium Carbonate in our ponds.

Why is it important to have a sufficient amount of Calcium Carbonate in your pond??  The nitrifying bacteria that remove harmful Ammonia and Nitrite from your water cannot survive without it!!  So, to put it simply, No Calcium Carbonate means NO BIOLOGICAL FILTRATION.  Without Biological Filtration your water quality will quickly become polluted and toxic for your fish and as a result your fish are much more susceptible to disease or even death!

What Happens if My KH Levels Get too Low??  The effect of low KH levels may not be immediately seen.  Low KH levels will ultimately lead to other water quality issues due to insufficient Biological Filtration.  A buildup of harmful Ammonia and Nitrite will start to accumulate in your pond.  Your pond will also be susceptible to harmful pH swings which could lead to a pH Crash, which could kill all of your fish very quickly.

How Can I Prevent My KH Levels from Getting Too Low??  The best way to prevent your KH levels from getting to low is to test regularly and adjust the levels as needed.  We recommend buffering your KH to a level of at least 150 PPM.  Some Pond hobbyists prefer to keep their KH level over 200 PPM.  KH levels cannot be “too high” however anything higher than 200 PPM is not necessarily of any real benefit.

How do I raise my KH Levels??  If you don’t have Microbe-Lift/KH Bio-Active Booster, then, regular Arm & Hammer Baking Soda will be fine in most cases.  This can be purchased at your local Grocery store for around $1 for a 2 lb. box.  However, keep in mind that the Microbe-Lift/KH Booster comes in 2 lbs., 8 lbs., 20 lbs. and 50 lbs. and contents are more stable, so may last longer in the pond than sodium bicarbonate.

How Much Baking Soda Should I add??  We recommend adding 1 cup of baking soda per 1,000 gallons of pond water daily until your KH level has increased to 150 PPM.  Test your KH level after 24 hours before adding more Baking Soda.

When Should I add more KH??  As needed, whenever your KH Levels Drop.  Be sure to test your KH levels at least once per week and especially after rain.  Rain is acidic and will lower your KH level.

What KH Test Kit Should I use??  We recommend using the API brand test kit.  It can be purchased at many pond shops or Amazon.com.