When I was about 13 and we first moved to Alabama in 1976, the 1 1/2-2 acre pond on our place had a few catfish, a ton of red-eye bream, and pond shiners or roaches that grew up to about 16" long. We added a couple grass carp and 11 small bass from another pond. There are no more shiners, now, and the bream population has stabilized and produces some real decent fish. The bass grew like they were on steroids for about the first 10 years or so, then leveled off, too. Haven't fished for them there in a long time, but I assume there are still some there. My Mom feeds the bream daily, when she goes down to feed our ducks, so we see them regularly. There are still a few big catfish in there, and the last of the grass carp was last seen just a few years ago, and was probably in the neighborhood of 75-80 lbs, then. Biggest bass I know that came out of it was about 5 lbs or so, biggest catfish is 27 lbs. We've introduced shellcracker a couple times, and have caught some up to about a pound, but they've never really taken hold like the bluegill and the bass. I've thought now and then that it'd be nice to have a place to put crappie in, but I've seen the damage they do to a micro-system like a small pond, and I'd rather not have to start over like we had to with all the small bream and shiners infesting the pond.