I have two solar panels for my pool. I have them piped to through one of the returns right now and I can control the flow rate to that return. My question is this: Is it more efficient to run a higher flow rate or a lower flow rate through the panels? I would assume that at a higher rate, the water coming out would be at a lower temp since it is not in the panel as long. And at a lower rate the water would be hotter since it is in longer. Would that mean it it doesn't really matter the flow rate?