Brian, I have no experience clearing a pond with gypsum. Don't fall for the bale of straw or barley thing either.

Read the 2 threads in the muddy water section about alum kicking clay's butt.


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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).