I am not an expert because I don't do much myself and I only have comets. However, some people use a shop vac or similar to suck crud off the bottom. Others drain part or most of pond to be able to reach and grab or rake some crud after removing fish to a separate area. I have a stream as well as pond. After removing overgrown plants or whatever, it stirs up the bottom. Part of this suspended crud gets pumped to the stream where it gets caught in the great tangle of stream plant roots and other junk. I often pull some of this crud from the stream. My pond and stream are always clear except after one of these activities. vansanst, unfortunately, I don't think any of us really understand the direct cause of fish death. I suppose you m.ight be in the best position to give some advice. If you found a specific pond test to be severely out of normal range it might point you or us in the right direction to prevent future death. Or perhaps not. It seems to me that over the years, many of us have done things that others said could cause trouble without in fact creating that trouble. For example, I have disturbed long standing bottom crud; had my pond completely iced over an inch or more for a month; and left a pond completely undisturbed with no circulation for years at a time, all without problems.

Very untrue, assuming the koi didn't actually die in the long winter. That would certainly explain no offspring. It can be amazing what people will imagine and say out loud.

Vicki, I just bought fall and spring food for my koi and goldfish as well. The fall/spring food is for temps from 55 or so to 65 or so, and the difference is the protein content. The fall food should have much less protein and much more carbs. My fall food has 11 % protein, while the summer food had 36 %. I don't think it matters so much what brand it is, just check for the temperature and protein. It's on the back in the small print. :) Mary

I have overwintered fish before, successfully, but it needs to be done in the basement on a cement floor. Filtering is easy, the only cost is a pump. 1. You find a large heavy plastic container, a Rubbermaid storage container is perfect or a tall barrel often sold as a rain barrel. 2. Set this container onto something that raises the bottom of it as high as the side of the pool. I used cement blocks to build a stable base for mine. 3. Put a drain hole in the bottom of the side of the container so the water can drain out into the pool. I put my cement blocks and the entire thing inside the pool but you can put it beside the pool as long as the water drains out the hole in the side bottom and into the pool without leaking onto the floor. 4. Fill the container with filter media of some kind. There are a lot of things you can use for this. Plastic dish and bath scrubbies work well(ones without soap), as does clean lava rock with no additives. Anything to increase the surface area for bacteria to grow on. (Quilt batting is too dense). You want to establish a good bacteria culture in the media. It is this bacteria that removes the ammonia from the water as it flows through the filter. This really doesn't take two months. Two weeks is more like it, especially if you seed it with bacteria from another fish filter, either pond or aquarium. 5. Run the pump inside the pool sitting on a brick, with an output hose that runs the water into the top of the plastic filter container. If you are indoors and there's not a lot of splashing, you won't need a lid on it. The outflow hole in the bottom side of the filter container needs to be four times the size of the inflow hose. If it is not that large, the filter will slow the water down enough to cause it to overflow. Filtering a pond is really very simple. You don't need anything more complicated than the pump. Get a pump that moves the gallons through the filter about four times a day. That will be your biggest or only expense. I use this type of filter for my outdoor pond too. An out-of-pond filter like this one works much better than an underwater pump filter. It doesn't have to be ugly plastic. I had one that was in a huge terra cotta pot and I put a few impatiens in the top. (yes, ordinary garden impatiens love growing bare root in water). It is called a "trickle tower" filter. Google it and you will get a lot of information. Rule of thumb for fish is this: one gallon of water for every inch of fish, including tail. If you have a super filtration system, you can get away with more. They will grow through the winter if your water is warm enough. I would also add a lot of plants to the water to help keep it healthy. One that I like a lot for aquariums, doesn't need much light and the fish don't eat it: Creeping Jenny! (Yes, the same ground cover with yellow flowers in the garden). I grow it in my pond too, in the pots to hide the rims. Just root pieces in a glass and stick in water bare root with a little rock to hold them in place. One word of caution: Putting koi in a 2' new home will usually cause them to jump out. If they have been sitting out on the floor, even overnight, just put them back in, even if they look dead. They will probably recover (here speaks the voice of experience).