There has been a lot of discussion about fish getting hook shy and learning all too rapidly. It seems like 5 acres would be big enough but I'm not at all sure. Read some of the past posts and you will find that some of us are just not catching the fish that we know are there. You might have the same problem. To answer your original question, it is usually wise to start culling everything below 12 inches after a couple of years. However, if you think you have a problem, it would probably be wise to get an electroshock survey done.
