I plan on building a 125gallon biotope similar to that of the Upper Tennessee River, specifically around the Fort Loudon Dam area (Near Knoxville). My plans are to have a few Pumpkin Seed, Bluegill, Crappie, and one or three striper white bass. From what I understand though is that these fish are very messy. Unfourtunaly, these fish make tasty snacks out of most of the bottom feeders, like crawdads and snails that would help to keep everything clean and tidy (It's how the larger bream like pumpkinseed and bluegill got their nick name of "Shellcrackers".) Also, all the catfish that are local to the area grow up to average sizes of over 20 inches. I just can't bring myself to put a fish that needs to get that big in such a small aquarium. Does anyone have any insight on a bottom feeder that wont be turned into a snack by the all the fish I plan on having?