5 Things to Know About Lowering High CYA in Your Pool

Partial draining is the only fix No chemical, additive, or filter media lowers cyanuric acid. Only dilution with fresh water works.

CYA builds up from stabilized chlorine Using dichlor or trichlor pucks adds CYA that doesn’t evaporate or get filtered out. Once over 70–80 ppm, chlorine becomes less effective.

Calculate how much to drain If CYA is 150 ppm and you want 50 ppm, replace about two-thirds of the water. Use the formula: 1 - (target CYA / current CYA).

A submersible pump speeds draining It moves water faster than a standard pump. Test CYA first, do the math, then drain accordingly.

Prevent future buildup by switching chlorine sources Use liquid chlorine or a salt system as your primary sanitizer. Reserve pucks for occasional use only. Check local water restrictions before draining.