I fish a pond that is spring fed and was wondering if there can be a detrimental effect from having too many species. The pond has bluegill, large and smallmouth bass, catfish, redhorse sucker, perch, crappie, brown and rainbow trout. I am sure there are a few other smaller species to such as minnows and what not. You can catch the gills all day long and the trout are reliable (bows more than browns), everything else is pretty tight lipped. It is maybe 1/2 acre pond and one of my favorite places to fish. I am glad to have all of them in one place but was just curious.