I have a 32500 galloon pool with Pentair VS Pump. Pump is below grade and a long run to the pool (about 50 feet). When I set it at a very low RPM <1800, I feel no appreciable movement of water from the 6 different outlets but I do see water movement in the filter basket (barely) and movement of water in the pot at the pump. So I know water IS moving but with MINIMAL perceptible flow at the outlets. I do NOT have a flow meter but wondering out loud how much flow I really do have? Is there a minimum pressure and flow that is needed to overcome head pressure?