I have an above-ground pool with a sand filter system. The intake is about 10 inches from the top edge of the pool and the pump is on the ground. When the pump turns off, water rushes back through the intake and shoots about 2 feet in the air. Whatever debris has collected in the basket shoots out into the pool again. Does anyone know why this is happening? We have change the sand recently and clean out the pump filter daily. Thank you!

Pool & Spa - Water Pik - Flow Valve Assy. Series II Bronze 325