We have a 1/4 acre pond in northern Indiana and last spring I put in 25 tilapia to eat FA...which they did very well. I understand that they are warm water fish and don't typically survive winter. However, we have an open loop geothermal system for our house and the discharge water goes into the pond. It is far enough away from the house that the water is ground temp by the time it gets to the pond...so 55 degrees. Have any of you had experience with a "warm" water supply helping tilapia survive a cold winter?

On a similar note what is the best way to fish them out? My understanding is that they are vegetarian so will they strike at a worm?