JKB, how are you going to tie the corners together, and how high are you planning on making the beds?

When I work with dimensional wood, I try to make my dimensions multiples of 24" to minimize cutting and wood waste. i.e. 243" dimension would be 240", etc.

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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).