Stocking fish is fun. Once you put them in there, healthy fish disappear. You won't likely see them again for a while unless you feed them. Your fish are still there.
Right now, all the signs of life are below the surface.
Fathead minnows eat tiny things, such as decaying leaves, small bugs, plankton, etc. It's amazing how fast a new pond in this part of the world develops a food chain for tiny fish.

Teach a man to grow fish...
He can teach to catch fish...