My neighbor has a 1/4 acre pond. One pair of Pekin Ducks kept it muddy so you couldn't see 12" into the water by dabbling all along the shore. He got rid of the ducks and within a month the pond cleared right up.

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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).