5 Things to Know About Stabilized vs. Unstabilized Pool Chlorine

Stabilized chlorine contains cyanuric acid (CYA), which protects chlorine from sunlight breakdown. Unstabilized chlorine does not.

Use stabilized chlorine for outdoor pools. Without CYA, the sun burns off chlorine in hours, forcing you to add it constantly.

Use unstabilized chlorine for shocking or indoor pools. Too much CYA buildup locks up chlorine, making it ineffective.

The trap is using only tablets without testing CYA. Stabilizer doesn’t evaporate, so after a season, CYA can hit 100+ and your chlorine stops working.

Switch between stabilized and unstabilized based on need: tablets for maintenance in sun, cal hypo for shock, and test CYA monthly.