I don't know. I have the manifold with pressure gauge ready to install on those windmill aerators, and I should have pressure readings later on next week. It was too cold yesterday to install them, the high was only 9�F here.

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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).