I keep reading this in articles/guides from the pool industry (even the manual for my chlorinator) but has anyone actually experienced this first hand? I assume it happens when you let your ph go above 8 for an extended period?
Does high pH really block out your chlorine?
- Thread starter LL Pool J
- Start date
Welcome to TFP!!!No. pH has nothing to so with protecting the chlorine from the sun. Cyanuric acid (CYA/stabilizer) protects the chlorine from the sun.
High pH is not good because it increases the risks of scaling both in the pool and in the SWG cell.
I think what they mean is that at higher pH the active chlorine (hypochlorous acid) level is lower. Though that is true, it is far less true with Cyanuric Acid (CYA) in the water. As shown in the graphs in this post when the pH goes from 7.5 to 8.0 the active chlorine drops by about 50% if there is no CYA in the water, but with CYA in the water it drops by only about 15%.
I've never figured out that second graph (Chlorine Usage from UV at different levels). It seems to state that the higher the CYA level, the more the loss from UV, which seems exactly backwards as to why you put in CYA in the first place.