I have been in the slam process for 4 days. I have a 20,000 inground with a sand filter. The first couple of days were typical with having to add bleach to keep up fc level and backwashing when filter pressure rose. My CYA is 40 and fc is 20 - a little high. The last day and half the fc chlorine hasn’t changed much and my filter pressure doesn’t rise but the pool is still really cloudy. Why would the fc not drop and filter pressure not rise ? Seems to indicate not working ?