We opened our pool June 18th. It was cloudy but green. We shocked it. The next day we took the water to get tested... actually to 3 different places. They all pretty much said the same thing...chlorine block. We still hsve nnnot been able to break it. We've put in about 18lbs. of Shox, super chlorinated it twice with 5 gallons of liquid shock but still no good, although the difference between the free chlorine and total chlorine have gotten closer. We've had a lot of rain so a lot of fresh water got in the pool. They said to put 8 to 10 gallons of liquid shock in. Im trying not to do that bez I use the pool everyday for exercise therspy. The ph is 7.8, cyuranic acid is 5 but they said to leave it alone right now, pool is cloudy but can see the bottom. I vacuumed it last nught and put in algaecide and clsrifier so today its more cloudy. I think maybe I should change the cartridge becsuse maybe all the algae is tying up the chlorine. It does not have any order at all. Thank you for any help you can offer. The pool stores use a computer to test the water and I don't think the young kids that work there know much about water chemistry.