A friend of mine put about 15-20 - 1 to 2 pound blue cats into his 1.3 acre pond about 10 years ago. One was caught last year at about 35 pounds. He thinks maybe 6 to 8 are still in there. The pond is 15 feet deep and has about 300 acres of rocky hillside watershed, so it has good flow through the cooler months. That pond still (to me) seems overpopulated with 3 to 7 inch bluegill. It also contains CC and several bass over 4 pounds.