Hi folks, I'm having exactly the same problem as a previous post (milky white / cloudy water after opening and shocking) Using my sand filter and running for nearly a week, 20 hours a day with little improvement. Chlorine still a little high (around 5) and pH slightly low (around 7.0), alkalinity is good (80) and Cyanuric Acid is also good (approx 50). I've added 2 and 1/2 quarts of clarifier (in stages) which seems to help a little bit. When I assembled the filter top, sand looked a little low, but still around the 2/3rd's mark recommended by manufacturer. Pool is 18x33 oval with an 8 foot deep "hopper' vinyl liner. Approx 21000 gallons. I have the vac head in the deepend (inverted), a tip a pool owner gave me which usually helps clear the water faster, but this year, not so much. After running the filter for nearly 6 days straight, I'm finally able to see the bottom of the shallow (4') end enough to vacuum up the dead algea.
My question is: I have some leftover "Sand Helper" by OnGuard which I purchased several years ago. Does anyone know if this is equivalent to adding the small amount of DE mentioned in previous posts? Instructions on the package say to only add approx 1.5 cups (for my size filter), wait for filter pressure to rise to manufactures recommended max, then backwash and repeat. Added the dose, but filter pressure remains steady for over an hour (no increase). Added a 1/2 cup more and still no change. Curious if anyone has previous experience with this product or any other suggestions. Not sure if this has a shelf life. Also, wondering if instead I should purchase more Clarifier and try that, or if there's a limit as to how much Clarifier you should use. Thanks in advance.