I agree with contacting Matt.

Bill, I had 4-6 Tilapia in a 4' sq. cage and there was no scrubbing required all season. They suck the FA from outside the cage to inside and eat it. I think where it's legal, having a half dz. Tilapia in a cage with other fish will eliminate any FA problems on the cage.

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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).