Welcome to the forum. Make sure the whole pond bottom is compacted properly with a sheepsfoot roller to ensure that it won't leak, and make sure that the clay has enough water to compact it, but not too much to make it soupy.

Another thing to consider, is that if the pond is 3:1 all around, what area of the pond will the BG spawn?

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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).