That's the nice thing about Fluridone, just dump the correct amount in the pond and walk away. It kills the weeds over a 30-45 day period. You have to treat the whole pond at once though. The dosage that kills the CLPW won't affect other native plants.

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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).