Brian, if you're not using it for a water source, then I'd go with the Cutrine granules. It seems to work better than the Green Clean type of product in deeper water. I don't think you can get the GC down by the Chara and still stay active for a long enough time.

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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).