Can't maintain chlorine level

Peggy Coleman · Postby **Peggy Coleman** » Mon 02 Jun, 2014 13:52

We have a vinyl liner pool with 35,000 gallons water. We have shocked the pool several times with as much as 13 bags of shock and have also used liquid chlorine but we cannot hold a chlorine level. All other numbers are perfect. We have an automatic chlorinator set at maximum too but still no chlorine level. Please help. Churchville, PA. Thanks.

Postby **chem geek** » Tue 03 Jun, 2014 14:45

What kind of "shock" was it? If it was Dichlor, then you increased the Cyanuric Acid (CYA) level and that reduces chlorine's effectiveness.

Also did you just open the pool having it "let go" over the winter? If so, then bacteria may have converted CYA into ammonia which creates a huge chlorine demand. If you aren't measuring any Free Chlorine (FC) but you see Combined Chlorine (CC), then that may be what happened.