sprkplug, I don't have an answer for you. When I was running the aerator, I could treat the weeds because the aerator was in the deepest part of the pond, and the weeds were growing shallow. I would treat about 1/3 of the pond at a time.

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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).