I have a pentair TR-100 and a pentair Inteliflo VS (3hp) pump. I have installed a Flovis check valve / flow meter between the filter and heater. I think the pump is capable of 140 GPM. I'm sure this is the max under optimal conditions, but it will peg the flovis at 100 GPM pretty easy. I believe the max flow for my valve, filter, & heater is 125 GPM. My questions are, what is the max GPM I should ever run under any circumstance? What is the optimal GPM for the sand filter to work best? I understand slower is better for the filter. If I understand right more flow is slightly more efficient for heating than less flow. Is higher GPM better for backwash/rinse? If so, how much? I have 2" sch40 everywhere. Thanks for the help!