I'd put the seed down this Spring to 1) help reduce the amount of sediment that is washed into the pond and 2) I believe you'll have less weeds to deal with.

No need for GC. Wait until you have weeds that you can't live with, then make sure those weeds are on the GC "like" menu.

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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).