We have always been taught that pH controls the strength of chlorine. And that's true, except when cyanuric acid is in the water too. CYA changes the entire dynamic. Fair warning, this topic is controversial and contrarian to most textbooks and industry beliefs. But it is backed in science that we will cite in this article. Buckle up.
CYA affects chlorine
In the event of an Accidental Fecal Release (AFR), the CDC has published a recommended limit to Cyanuric Acid (CYA) at 15ppm for commercial swimming pools. The vast majority of outdoor pools in America have far more than 15 ppm of CYA already, so what can be done?