Also, alkalinity won't change overnight. Check it again in a few months. Just like adding lime to soils, here they recommend doing soil tests in the Fall and liming in the Fall if needed, so the soil pH will have changed by the Spring.

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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).