Pressure issues Sand Filter

Have a Pac-Fab (Pentair) Sand Dollar (SD-40) sand filter. It originally came with a 2hp motor. After first season I repleaced with a 3/4 hp motor. The pressure gauge always reads 18 pounds. By the time it reaches 20 pounds, I have to backwash because the flow through the skimmer and out return are minimal.

After backwashing, the water flows out of the return with the flow of a high powered powerwasher. This has been a problem since day one, the high pressure return flow. I tried a Polaris 65 auto cleaner and by the end of the season, the inside mechanism would wear out due to the pressure.

I backwash based on flow, not pressure. Yesterday I tried the de powder. I raised the pressure 1 pound. When I went out this morning, there was virtually no flow coming out the return. Backwashed and now have a high pressure power washer again. Any help would be appreciated.

I am assuming that your pool is an above ground. You might be able to install a larger inlet eye ball the one you have could be to small for the amount of flow that you have. The Polaris 65 has a pressure relief valve on it so you can reduce the flow to it. If you have the larger type eye ball inlet and you still have to much flow then just add another return to the pool so you do not have so much flow coming out of one return. I would not add DE to the filter unless you have a water quality problem and if you do have a water quality issue then check your chemistry first.