Air is surging back through the skimmer when I turn the pump off. It is causing an eruption of water out of the skimmer. This results in low water in the pump basket that I have to then refill before turning the pump back on. I have tried bleeding air by holding down the handle, I have backwashed and rinsed several times, and I have done a deep clean of the sand in the filter. I don't see any leaks in the intake hose that would suggest it is sucking air from there. Hoping someone has an idea of what is letting air into the system. I have a Jacuzzi Lazer Sand Filter.