I have a 24,000 gallon in ground pool. This spring, I have had some problems getting it started. First, the pump failed to move any water, so I replaced the gasket, added some more lube to the O rings, and tightened a few things. Now the water is flowing and doing so without air. However, one of the returns is producing no water flow. Both skimmers and the drain are providing water, so the problem seems to be on the pressure side of the pump.