Review on 🐋 High-Performance Whale Inline Valve - Ideal for Suction or Discharge Lines - Enhanced Nitrile Material by Jon Cherian

I bought this for my bilge pump because there is quite a long hose from the pump to the outlet. Without a check valve, all the water in the hose would flow back into the bilge after the pump stopped pumping. But there is a small trickle that flows in the wrong direction, rendering the check valve completely useless. This. it takes much longer, but all the water in the hose ends up back in the bilge. Shouldn't that prevent the non-return valve on the bilge pump?