This same thing happened to me last year and the pool store ripped me for a mint!! My pool started looking a tad cloudy on Monday, no today (Wednesday) its so cloudy you can't see the main drain. FC - 4.2 TC - 4.3 PH - 7.5 Alk - 110 (pool store values concurred). What is the deal??? Please Help!! My son's Birthday/swim party is right around the corner!!!!