It would be easier down the road to manage two individual ponds than one large one. You could have different species of fish in both, maybe species that would not do well in a pond together. Say, LMB in one, SMB in the other? Or make the smaller one a kids fishing pond and the larger one for adults?

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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).