Welcome to the forum. I''ve never had that around here, but since it's the holidays some of the experts may not check until tomorrow.

When you say rust, I'm assuming that your water has a high iron content. Do you know what the iron content is?

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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).