Thanks for your timely response.

Unfortunately I inherited the pool when I bought the house and don't have a manual. The grids look fine, I'm just looking a solution to the pressure losing problem. Honestly, they look very good when I hose them off.

MY pool was almost blue last week and then we got hit with 4 inches of rain which messed up the chemical balance of the pool. We have had almost 12 inches of rain in CT in the last couple of weeks so getting the pool ready has been a challenge. I'm just trying to figure out why the pressure on the pump in good for about an hour and then just drops down.
The pool is really green right now and I have backwashed at least 7 or 8 times. Could it be the algae that is making the pump lose almost all of its pressure withing a couple of hours? An impellar clog (we did vacuum a lot of leaves when we first opened the pool) What should I do first? The pool store just want me to keep buying more and more chemicals. I need a plan.......thanks for your time.