I have created a passive solar power system by creating a bypass between the filter output and pool return. The solar system is 400' of 1 1/2" pipe so it makes sense that the pump isn't powerful enough to force the water through the 400' of pipe (there is a significant drop in pressure at the return).
I would like to add a second pump that I only run when I have the bypass open, but don't want it to be so powerful that it pulls the water from the first pump. Do you have a recommendation on a secondary pump for this configuration? I was considering a 3/4hp pump figuring that would be enough without impacting the primary pump. If so, any idea of how long I could make the coil (I can always add to it) and still handle it with the secondary pump?
Thanks!