The only downside to putting an aerator in a small pond is if you normaly would want to ice fish the pond. The aerator might make all of the ice unsafe to walk on. But I feel that the positive things that an aerator will do for your pond will outweigh that one possible negative.

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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).