I am concerned about the low pressure on my sand filter. When running on low it is about 2.5 psi. When I turn my pump on high it is around 11 psi.
I am getting good flow back through my return jet. Is it possible that not enough sand was put in my filter when it was installed? It is a 22" filter, and the installers put 150 lbs of sand.

Is there anything I can mess up by taking the valve off the top and looking into the filter to see how much sand is there? If I do, how high should the sand be?

Thanks

Tim