Calculate how much cyanuric acid (CYA) stabilizer to add to your pool. Ideal CYA level is 30-50 ppm to protect chlorine from UV degradation.
Enter current and target CYA levels to calculate the required cyanuric acid dose. The ideal CYA range for traditional chlorine pools is 30-50 ppm.
CYA protects chlorine from UV degradation, reducing consumption by up to 50%. However, high CYA (above 80 ppm) significantly reduces chlorine effectiveness.
The only reliable way to lower CYA is to partially drain and refill the pool. Trichlor and dichlor tablets contain CYA, so CYA levels naturally rise with their use.
Cyanuric acid (CYA), also called pool stabilizer or conditioner, protects chlorine from UV degradation. Without CYA, sunlight can destroy 75-90% of your pool's chlorine within 2 hours. With 30-50 ppm CYA, chlorine lasts much longer, reducing chemical costs and maintenance frequency.
The ideal CYA range for outdoor pools using traditional chlorine is 30-50 ppm. For salt water pools, 60-80 ppm is often recommended. Indoor pools don't need CYA since there's no UV exposure. CYA above 80 ppm significantly reduces chlorine effectiveness.
Add granular cyanuric acid by placing it in a mesh bag or sock and hanging it in front of a return jet. Do not add it directly to the skimmer. CYA dissolves slowly — it may take 24-48 hours to fully dissolve. Retest after 48 hours.
The only reliable way to lower CYA is to partially drain and refill the pool with fresh water. There are no chemicals that effectively remove CYA. To prevent CYA buildup, avoid using trichlor or dichlor tablets as your primary chlorine source, as they contain CYA.
High CYA (above 80 ppm) significantly reduces chlorine effectiveness — this is called 'chlorine lock.' Even with adequate free chlorine, the water may not be properly sanitized. If CYA exceeds 100 ppm, partial drain and refill is strongly recommended.