Okay, here's the deal. Bought the house with pool already installed. Including a 'grotto' at the deep end. The grotto is sandstone with a big slab of sandstone over the top. The problem? The pool builder used stone that is REALLY soft, that is, it sheds fine grit and flakes constantly. The Dolphin pool cleaner picks up a healthy handful every time I run it, no matter how often - back to back cleanings, same result. Plus the Dolphin stirs up the sand, so it's cloudy for hours. Sand builds up on the splash pad and seats within hours of vacuuming. Grrr...
New cartridge filter system last year. The sand got old, then the upper housing cracked, so it was ready to replace.
I'm considering adding a separate bypass filter to filter out the smaller/tiny grit - like 5-10 microns. At a previous house I added 20" tall water-filter housings for whole-house filtration, one for sediment and one with charcoal. Seemed to help. Anyway, I screwed up and bought the wrong size filters, so I have two HUGE filters, 20" long but 4-1/4" diameter. Cheap enough they weren't worth returning.
Now, I'm thinking about buying the correct size filter housing, and plumbing this extra filter to catch the really fine stuff. The big housing is under $65 with no filter included - McMaster-Carr.
Obviously it can't take the GPM of the whole system, but plumbed in bypass maybe 5-10% of the water would go through it. Over time it should catch the fine stuff the big cartridges won't.
Thoughts? The only other solution is to tear out the grotto and rebuild it with better stone. The house is some kind of sandstone too, but it holds up just fine. This stuff is so soft a garden hose creates a river of reddish silt. Ugh.
Thanks!
c.