Aeration will not combat algae. Gast 0523 pump will produce approximately double the cfm at 5 psi while using half the electricity that the 87R will generate. . Your pond will produce roughly 5 psi back pressure at it's deepest point,

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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).