Tilapia would compete for space, and with males and females spawning in a bluegill pond you'd end up with lots of tilapia. If you are harvesting this pond anyway every fall or so to supplement elsewhere, you'll find that this is a perfect scenario. Stock tilapia in early June and raise more fish per acre than with bluegill or tilapia alone. Then tilapia die in winter and you'll have bluegill left over to spawn in the spring before adding more brooder tilapia.

It's ALL about the fish!