Liquid for surface, granular for bottom growing. I'd use granular in water more than 3' deep, but I want to see what the experts say before taking that depth as gospel.

Make sure that the deeper stuff is really algae, or it won't work on it.

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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).