I need to replace my pump and motor. I am considering the Pentair 347990 Opti Flo 1hp 2 speed 115v or the Hayward SP15922S Power Flo Matrix 1HP 2 speed 110V. My sand filter is 2sq ft and the pool is 7700 gal above ground. I am running the Liquidator on it. I have read where the Hayward has a higher flow rate. So, my question, which one of the pumps will have the best chance of working the Liquidator on low speed? Thanks for any input.