To me, the fish that does NOT have the cutout in the dorsal fin is a bit underweight. I would have removed that one to leave more food for the other, faster growing fish. Or, it's just the camera angle that makes it head seem slightly out of proportion to its body.

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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).