I currently have a Fox Wall-Pak cartridge filter and am considering switching to a sand filter because these cartiridges have been a pain for me and have led to some cloudy conditions in the pool this season.

Essentially, in the filter housing, I have 2 cartridges, 1 for the skimmer intake and one for the main return intake at the bottom of the deep-end. The pump is about 15' away on the side of the house. It's a 1hp pump. There's also a chlorine feeder next to the pump in the return line, but this pool was using biguanide, so the feeder is just in the loop.

Where would the sand filter go, before the pump or after?

Is this too big a job for joe do-it-yourself?

What about the Wall-pak? Keep the housing to use the skimmer but ditch the cartridges?

Any comments suggestions would be great.

15000gal inground rectangle pool...