Unless there is something in the pond or getting into the pond on a temporary basis that is stirring up the clay.

A neighbor had turbid water in his 1/4 ac pond. One single pair of Pekin Ducks was the culprit. Coyotes got the ducks, the pond cleared up in a few weeks.

www.hoosierpondpros.com

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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).