Chelated copper will remain more active but when you consider that a lot of algae is being spot or perimeter sprayed the dilution factor is great thus lowering its capability to have much of a residual or potentially lethal effect. To acquire much residual you would have to use the labeled calculations for treating acre feet vs surface mats.With a lot of ponds getting turned over 1-3 times per day copper sensetive fish may be safer that unaerated ponds also.
