Time to chime in,I have permission to fish a pond that only two more can fish and I would class them as don't worry they won't catch much.The owner now is the son of the man I got permission from 20+ years ago.It is 7 or so acres and has bass crappie carp to control grass and shell crackers and a few species of bream.When his father owned it I was the only one to fish it.I could go and catch 30-40 bass in 2-3 hours the largest caught 9lbs 4 ounces.Since his death the son has been less than alert on keeping the pond from slip ins and the bass have been taken out and now the panfish have started getting smaller .I have been throwing them behind the spillway to swim downstream but it only helps slightly.If I were to stock crappie in a pond,one the pond would have a minimum depth of 20 foot deep and be at least five acres big with bass in there to help control the panfish.I would also cull and keep smaller fish.