O.K. I pretty much have desided to buy a new filter. I was looking at 2 different types. The hayward star clear c500(cartridge)and the hayward sand s166t and s180t. I have a AG round 24'x 4' deep. I believe that the volume is just under 14000 gallons. (If somebody could verify that I would appreciate it.) Any how, I have a magnetec 1hp motor and was wondering if I need to change the motor also, or can i still use thie one I have. I don't know the specs on this motor, but it is 1hp. TKS!!!!