I came up with the same figures you did, just under 2000 gallons -- but that is if you're not going to have shelves. Shelves reduce the water volume, so to get the almost 2000 gallons you would need to go wider or deeper to compensate.

The rule of thumb for a water garden with koi is one fish per 250 gallons. Optimum conditions call for 500 gallons or more per fish, but most don't adhere to that strictly. Some keep koi in as little as 200 gallons per fish. The key is keeping the pond in balance. So, with a roughly 2000 gallon pond, which is almost 500 gallons per fish in your pond, I see no reason why you shouldn't be able to keep your four or five koi with no problems.

Large koi do eat plants, but I have nine koi and kept four waterlilies in my pond last year. They like to root around in the gravel or sand that people use on top of the soil to keep it in the pot, and people with shelves often find that the koi have knocked the pots off the shelf. Koi love hyacinth roots, so expect them to make short work of those, ;-).

What you might want to consider is adding a bog pocket for your marginals in a corner or two where you have extra liner (instead of shelves). You just dig out a hole about a foot deep right up against the pond with the edge just below water level, so that the pond water can get into the pocket. You can separate the bog from the pond with a few rocks placed along the lip. Place your potted plants in the pocket and fill with gravel up to the edge of the pots. Or you can bare-root the plants in the gravel, but mine seem to do better in the pot where I can easily add fertilizer to the soil. I have bog pockets and I keep cattails, blue pickeral, star grass, and black magic taro. Cannas do great in bog pockets. The fish can't get to them to bother them or knock the pots over because the pots are "outside" the pond.

You shouldn't have any trouble wintering your koi in four feet of water. Most people use a deicer or a stock tank heater, which keeps a hole in the ice for gas exchange.

A UV clarifier is something that is a personal choice. Some people like them, some don't. They do a good job of killing suspended algae, but will not kill the algae that adhere to the liner. They DO NOT kill beneficial bacteria unless the bacteria has not had a chance to settle, so if you get one, leave it off for a few days if you plan to add bottled bacteria. The UV kills anything that floats through it. Bacteria adheres to the liner and the gravel in the stream bed. Some people report that they have had great success with using "Nu-Foam" in their skimmer to trap suspended algae, and that is something you might want to consider if you don't want to get a UV. I've never used it before, but I just built myself a DIY filter, and I'm going to use Nu-Foam in place of a pre-filter mat just to see if it works. You can get it in the sewing department of Walmart.

Happy ponding!

Thanks for your help, Nancy!
I actually have a friend that is getting rid of their 3000 gallon koi pond, so I might be able to get some nice big (20") koi from her. To introduce the fish, would you recommend doing it one fish at a time over the course of a few weeks or all at once when the pond has cycled for about a week or so?

Those bog pockets sound interesting, so I might try one on the side of the pond. I was thinking that I might just put a few shelves in the pond like one on the waterfall side of the pond, like a little protrusion from the sidewall. This could satisfy my want for shelves, and maximize the possible gallonage of the pond.

Would you highly recommend the use of a bottom drain for koi?

I HIGHLY recommend the use of a bottom drain for koi. My pond is 9000 gallons and the bottom always stays clean. Pond maintenance for me is just flushing the filters once a week....I don't even get my hands wet. Bottom drains make the environment much healthier for the fish, and make maintenance much easier as well.

As far as cycling....it's going to take 5 or 6 weeks for the filters to cycle. You can speed this up by borrowing some of your friend's filter bio media and stick it in your own filter. In fact, since your pond is not done yet, get some bio media and have her keep it for you in her filter. It will get seeded with bacteria and when you get the fish, take the media too so you can get a HUGE head start on cycling. I would not start out with a heavy load on the pond. Get a couple fish and then wait maybe a month before adding the rest. Keep a good eye on ammonia levels while the pond cycles.

My pond does not have a bottom drain, so I'm going to have to disagree with those who say that you can't keep healthy koi without one. However, there is a bit more work involved. I have a Pondovac 3, which I use to vacuum out the stuff that sinks to the bottom, usually once every month or so, but I'm told that a shop vac can be converted. I bought my vac on eBay. They come up occasionally for a pretty good price.

A bottom drain does reduce the labor involved with keeping a pond clean, but most ponds in my area do not have a BD. I am installing a homemade filter this spring to help pick up the debris.

I would introduce just a couple of fish initially. They like company and do better when they're not alone. Check the water with test strips to make sure everything is staying normal, then in a week or two, add another fish or two.

Does the bottom of the pond have to be very sloped in order for a bottom drain to work, or would it be fine if the bottom just was on a slope of a few degrees towards the drain? Would I want to connect the bottom drain to my pump?
I need to know about the ice resiliency of the EPDM pond liner. Could it possibly be torn or cracked by the expansion of ice? I would think that the liner wouldn't be effected by the ice since it is rubber, but I just want to make sure since this was a concern from one of my pond friends in the south.

For jump starting the biofilter by putting the medium in another pond, could I just use a trashcan and add some microbe lift to the water? Would this simulate the effect that beneficial bacteria has in a pond to attach onto the media?
If I get high ammonia in my pond, are there any chemicals/treatments that I can do to remove the ammonia. I know that I had a huge ammonia problem with a 10 gallon fish tank, and it took easily 1 month+ to clear itself up. Would plants help to remove ammonia/nitrates during the cycling period?

Sorry I am bombarding you with all these questions, but I want this pond to succeed over the long run, and have happy koi.

Oh, and here is a picture of my site:
The black hole is an estimate of where the pond will go, and the pine tree wouldn't be close to the pond, so there is no worry about falling leaves.

{{gwi:191018}}

Thanks for all your help!
Nick

Go bigger. Everyone I know has regrets about not going bigger. Get a UV filter. Your water will be green the first of many months. you can avoid the hassle and wait with a UV clarifier. Good luck.

I'm not an expert on bottom drains, but my assumption is that the bottom does need to be sloped toward it for it to be effective. I would say probably more than just a few degrees. Bottom drains are the most efficient way of keeping the bottom clean. I don't have one, but if I ever get lucky enough to build a large pond (Gonna have to win the lottery for that!), I would probably install a couple of them.

I've never heard of anyone's liner being torn by expanding ice, so I would say it's probably rare. Just make sure you have some kind of deicer to keep a hole open for gas exchange. Never use a hammer to open up a hole -- if it closes up, use warm water as many times as it takes to open it up again.

If you decide to start your bio bilter in a trash can, you'll need something to keep the water moving, like a small pump or an airstone placed under it. You will also need something for the aerobic bacteria to feed on, i.e. fish poop.

If you do get an ammonia spike, first do a partial water change, being careful to remove the chlorine from the fresh water. When that's done, add something like Ammo Lock and an airstone. You will still have ammonia, but the Ammo Lock detoxifies it. Stop feeding the fish for a few days and remove any dead plant debris.

Thanks for all your help everybody! I'll post progress pics when the time comes to start the excavations!

Nick

P.S. Should I get the Pondmaster Mag-Drive pump, or the Savio one?

Nick,
I just went through my first winter with an EDPM liner and no problems with the ice. As far as the pump goes not sure how gph you're looking at but I just purchased a Big Frog by Anjon 3000 gph at only 150 watts of electricity. I'm curious to know if anyone here has any experience with this pump>

I have a Pondmaster Mag 1200, but I haven't plugged it in yet. Will do so probably this weekend after some renovations on the pond. One of the reasons I bought it was that it was made in the U.S. Bought it from Bestnest.com. Good prices.

Do the Tetra 3" and not a retrofit. I would error on the side of a larger pump. Your pond will be the same size as ours. The koi actually help the bottom drain because they will stir up the bottom so everything eventually gets there. Our bottom drain goes directly to our pump (with strainer basket) then to filter, then to 40 watt UV light then to waterfall.

So here's what I have on the list so far:

Savio skimmer w/ 8.5 inch weir
Savio livingponds bio filter
Pondmaster hy drive 4000 pump
Pondmaster 40 watt UV clarifier
20 x 20 EPDM liner
3" tetra bottom drain

Does this sound about right?

Nick