Theo, the twenty acre lake is beginning to show some signs of eutrophication, but oxygen levels were great all summer. This summer the lake had its first real plankton bloom for a few weeks, enough that it had the water treatment guys worried about water flavor. But, the trout thrived.
The smaller pond is new, and water is fresh. That's why I am cautiously optimistic, and plan to follow it for several years.
jas...numbers are as numbers do. With trout, the more the merrier, up to a point. I would start with 100-150, feed them, and watch what happens. You will learn a lot. Each pond his its own merits, and that's part of the fun of pond management. You figure out what the pond will let you do, then manage it. I would stock larger fish, and feed them a bit.


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