^^^ What Bill said above. You want to apply the chemical in late May at the latest. You could treat the pond once for algae around the beginning of June when the water temp is in the low 60°F range then within a few days stock 100# of Tilapia TIlapia. That will take care of 90+% of the algae the rest of the year too. We stock a bunch of Tilapia for algae control, where in the state are you?

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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).