When replacing my DE Filter years ago I replaced it with a 90 sq Ft Hayward Cartridge filter after looking at the in-store brochures. A year or so ago when I had my pool resurfaced (guniite to fiberglass) they tried to convince me I needed to get a larger filter. I have a 15kgal in ground pool with a 1.5Hp hayward pump. I can get replacement filters @ Lowes for 50$ so its easy to keep extras around and I just swap out a clean one for the dirty ones. So are they right? Is my filter too small?
If so can anyone point me to the calculations so I can figure out the right size?
Thanks in Advance!