Need help on a couple of issues.

First: The drain for my pond is a 10" standpipe. I currently have a milk crate over it to stop trash. The problem is if leaves cover the crate, water stops flowing and the pond floods. Does anyone have recommendations of a good trash guard that allows water flow yet keeps my fish from going through?

Second issue: I stocked 1350 bluegill/bream in October, 30 carp in March, and 175 F1 bass in May. When will the bream be large enough to catch, and what kind of growth rate can I expect on the bass? The pond is not fertilized, and the fish are not fed. The pond was constructed last June, and is spring fed in a wooded area.