If you wrap the inside, when you use a net to get the fish out, they won't be able to hide behind the PVC pipe like they do when the netting is on the outside of the cage/pen.

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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).