Thanks Ben. Re timeline: the pool did not cloud with the addition of Phos-free. It was crystal clear when I added the product, and stayed that way for 5 days after. The Phos-free instructions are to run the filter for at least 48 filter hours without cleaning off the product and to keep the chlorine under 5 ppm, so I didn't add chlorine for several days. Then, after cleaning the cartridge filter I added my usual weekly 2 scoops of hth, and the water immediately turned opaque. It's been two-and-a-half days and the water is very slowly clearing. I can make out the bottom of the shallow end. I'm hopeful it will clear eventually without clarifiers. I don't plan to do this again, and I have ordered a Taylor kit.