advice on a pump/plumbing "circuit' I have an above-ground pool with a 3/4hp pump - enough to operate the filter. I want to install a solar heating loop in the system. (passive array of water pipes that pass pool water and soak up heat). It has dozens of feet of pipe and a head of as much as 8 feet. Clearly, my 3/4hp pump will be inadequate to keep the same throughput. The obvious solution is to upgrade the pump, perhaps to a 1 1/4hp or whatever. But I have this other 3/4hp pump lying around doing nothing. It would easily drive the solar panel. My question: Seeing as there is noly one inlet and one outlet to the pool, how can I hook up both pumps? Do I hook them up in "series" or do I hook them up "in perallel"? If in series, I worry that one's through put is differnt thant he other, and one will either "suck the other dry" or overload it. If in parallel, so I'd have to have a Y-junction at inlet and outlet. But now I've got unfiltered water passing through my solar plumbing. So I could split off the solar plumbing after the filter - but now I'm back to series. Maybe I need a series circuit with some sort of bypass? Advice?