Here is what I had posted regarding converting head loss to GPM:Originally Posted by ePoolUser
Next look up the flow (GPM) on the pump head curve for both high and low speeds. Low speed should be 1/2 of high speed GPM. Low speed head loss should be 1/4 of high speed.
Usually, the pump head curve is in your pump manual. The vertical axis is head loss and the horizontal is GPM.
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