I'd say 24" taller than the deepest area is a minimum height. I wouldn't be afraid to go 130% max depth for the height.

What size mesh? Well, I'd go as small as you can go. Bigger mesh will act as a gill net on the smaller fish, and you will lose a lot to handling stress.........8" and under LMB can eat a 4", maybe a 5" shiner........... Golden Shiners will reproduce at 3 1/2" to 4" in length. Do you have the proper reproduction habitat for them?

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).