Hello AK,
I am not a pool person I'm 100% new to this world, after all the repairs she finally got to the point of filling this pool in mid-June within 4-5 days we started seeing the metal ring on the vinyl liner waterline... Started working on that with metal removers and all that goes with that. The last chemical was Sparkle up then we saw a cloudy pool.
In CT. all the pool companies are booked the two companies who did the repairs and liner would not offer any weekly service. This is the main problem, so being newbies started with test strips running water to Leslie's and a science lab in town for well water testing. A month later I wondered about the sand since it was old she bought zeolite sand. My GF was angry about the back-washing so I stopped short of the time I wanted to do it. I did see some cloudiness right off but nothing like what the water ended up like in 24 hours.
That moved us into the next phase of more back-washing, more trying to remove the green water. We did a lot of research, tried many chemicals and filtering decided to remove the zeolite.
In the last week or so we bought organic sand and this time I checked about 2lbs in a 5 gallon bucket for dust and cloudiness and this was much better, except even after a long backwash/rinse I saw cloudiness the next day again... Up to this point we've flocked the pool 3x 1st two saw a lot of sediment now not so much the last time a few days ago saw nothing.
We started noticing some slime on the walls, going back over the tests we noticed the phosphates were high so in the last few days we've been working on reducing that and I do see some improvement. This is after the one pool guy came by and said to switch to a DE filter he said this was a filter problem not chemicals and this cloudiness will be gone in 12 hours if we buy a DE from him, but he wouldn't back that up with his wallet.
Our basic tests are all within range except the 1500-3800 phosphates this is a bromine pool so we don't have cyanuric acid.... Back to my original question is the Sand filter ancient relic that is no good or is the pool guy a hardcore salesman.