Artie:

The Copper Sulphate itself doesn't lower the O2 level, the O2 level drops because the algae that the CuSO4 killed died and is decomposing. The process of decomposition needs O2.

Talk to Nate about their bacteria. Also talk to him about whether you should be running the aeration system all year long.

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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).