In large #s yes they can cause turbidity.
Quite a few things starting to click here. I had been confused about this for a while when I feed the fish many of them did not look like bluegill to me but I've had murky water so I thought maybe the weird colors is lack of sunlight.
I've tried gypsum, and alum both. Neither did anything to solve my problem. I've pulled 40 or so out of the pond so far, but no telling how many the hawks have snatched up. Plus I expect there to be quite a few more when i go back. I'm headed back up there mid week to keep pulling them out so that I don't create a worse situation.
Now I'm not even sure how my actual stocked BG situation is as I haven't really seen them. I've caught 2 bass that were perfectly healthy and appropriate size in October. I assume they don't mind eating tilapia offspring.
I have no idea how I got Tilapia though so I'm guessing this may end up continuing to be a problem I need to deal with somehow. Guessing my resident blue heron is to blame. sighhh..
