hello all im in the process of overhauling my pool that hasn't seen sunlight in 3 years now the new liner came in today now im to the filter that i didnt think was doing the best job last time it was open so im open to suggestions here are my specks...18x33 above ground 15,000 gal. with center drain the filter is a aqua tools at3120 sand filter(2.18 ft2 surface area,44gpm filter rate,20 gpm filter rate with 200lbs of sand) which is a few years old running off a old 1hp jacuzzi pump...should i just change the pump out for a new higher hp motor? or change the whole set up?..also whats your input on these floor liners are they worth it? thanx