We obtained an above ground pool used that is 45' x 18' x 54". (Approx. 15000 gallons) We set it up last Spring. We have a pretty large sand filter, 200 pound. Based on the instructions this filter and pump came as a set together so I assume the pump should be fine for the filter. We have one inlet going into this pump. The pump basket always has a small air pocket at the top, the inlet is covered but there is air at the top. We get 10 pounds of pressure on the gauge, freshly backwashed and this is a new gauge. We get descent pressure out of the outlet. Our problem is we still cannot seem to get our Haward lady bug pool vac to move. It draws water from the bottom and rear port but it doesn't move around the pool.

What would normal pressure be on this system?

Is it OK to have a small air pocket at the top of the pump basket?

Or did we just get a bum unit. When we use the regular pool vacuum it works.