The nutrients in the pond that were utilized by the weeds are now feeding an algae bloom. Catch 22 situation. Like RC51 said, take your pick, weeds or algae if the excess nutrients aren't dealt with.

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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).