Over the years I have had many awuariums and ponds. During my 20 years on our farm, I had a small preformed backyard pond, a barnyard pond and a large pasture pond. Now at my current house with a small backyard I have been experimenting. I began with a large flowerpot, snails, crayfish and small goldfish. The goldfish from various pet shops are had diseases. I spent alot of time and money trying to save them. Out of about 15, I have 3 big beautiful survivors. They overwintered in a big plastic tote in the basement. They are now about 6-8" and growing. I have them in a 100 gallon black rubber stock tank. Running a sponge filter and an awuarium waterfall filter. Waiting on a Tetra submersible pump for the box filter that arrived earlier this week. I added water lettuce and hyacyith. They should start dividing soon and help with water quality. When I do water changes I use that in my garden. For those of you using box filters I would some input.