Ya know, plastic mesh is available from 3/16" openings all the way up to about 2" openings. That's what the fish cages are made of. No metal to rust, no zinc to bother the fish, no rough wire to damage the fish in the cages. It's available in rolls that are 4' wide.........

www.hoosierpondpros.com

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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).