Call the company and find out how toxic it is to the fish. Ask them for a Parts per Billion toxicity level (PPB).

I'll bet once you do the math you will find it's a non-issue.

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).