Bill, I think you are on to something. The clients pond that winterkilled a few years ago had 12" HSB and 1# RBT in it. All the HSB died, but only 80% of the RBT died.

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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).