While a few people have tried such products, there seems to be no consensus on how to ensure that it works the first time. If I remember correctly, more people have had success digging out the bad area and correctly re-packing good clay in the area in 6" lifts.

Search ESS-13 on here and read the results to make a decision for yourself.

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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).