What is causing my chlorine to lock up? I have put A LOT of chlorine in my pool this year but still cannot get a FC chlorine reading. My testing over the last 2 weeks says my TC levels ranged from 3ppm to over 10ppm for a couple days at a time but nothing in the FC levels. I've taken my water to the pools store and they confirmed my TC and FC levels, they also did a chlorine demand test. The Chlorine Demand test recommends a partial drain might be my best way to solve this because the chlorine demand is so high (somewhere is the range of 88lbs. of Cal Hypo).
They also checked Phosphates and that level was 1000ppb, but they told me that level wouldn't be causing this problem.
What could be causing this Chlorine Lock, no matter how much or what from of chlorine I put in it just seems to lock up.
Thanks in advance Marc
I have a 20K gal. In Ground Pool with a white plaster finish.
Total Alk. 120
Total Hardness 300