I have recently purchase a foreclosure that has a in-ground pool I'm used to above-ground pools 18 round my 48 in deep ... I am new to a sand filter Books-A-Million with cartridges instead of rinsing the cartridge or replacing with a sand filter you just backwash and vacuum to waste and of course not to forget to put it in rinse cycle before I filter! Hoping I can get some advice regarding my filter running normally and my pool level the water goes down so I have to keep the hose in it any advice would help!