It happens when you pump too fast and cant feed enough water to the pump because the intake is too small… was happening on a dingie prototype i was building… The problem with the pump is a) it will kill it faster b) cause micro bubbles…
i believe
what your describing would be directly related to the design of the pump. if you install your pump directly it should be a non issue.
okay, i posted some prelim plans in the remodling thread…