Originally Posted by Frickmiester
Ok. But wouldn't most of the water go back into the sump if I have the valve on the main return since the line going back to the sump would be the path of least resistance?
Yeah, but you don't want to slow the flow of the pump with a valve, it will shorten the pumps life span. So you keep a ball valve on the line to the tank, and one on the valve going back to the sump. You will simply have to tune the valves right and you will see, once you get it right, it will work great
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