All About CYA

CYA, or Cyanuric Acid, stabilizes chlorine products to prevent them from being deactivated by the ultraviolet rays of the sun. CYA is for pools only and should never be used in a hot tub, though CYA levels can rise when shocking with Dy-Chlor. 

The recommended level of CYA is 30-50 ppm and no higher than 100 ppm. To increase the level of CYA, one can add either granular or liquid CYA to the pool; however, issues can arise if CYA levels become too high. With high levels of cyanuric acid, chlorine is less effective which can lead to growth of algae and bacteria. Cloudy water can also occur if the levels are too high. If the CYA level is too high, one must drain and refill with fresh water to dilute the level. Though they exist, we at Hydra Hot Tubs & Pools don’t sell CYA removal kits because of the mostly negative results pool owners have had with them.

If one’s level of CYA is too low, the sun will burn out the chlorine. If one’s pool is in the shade through most or all of the day, then it is not recommended to add CYA, especially because it can also be found in chlorine tablets and the chlorine won’t burn as fast since the water is in the shade. So trace amounts from the tablets will be sufficient enough for their pool. Pools that get a lot of exposure to the sun are not required to have CYA added to them, but it can add longevity to the lifespan of the chlorine in the pool.