Florida, I found many pools and spas exceed the maximum state CYA levels.
I also found that techs had to battle with onsite management about the requirement to partially drain the pool. Frequently service techs would not drain the pool and retain the high CYA levels.
Problems would increase even further due to onsite management’s lack of education, further affecting how the tech managed the pool. Better education for onsite management would be beneficial.
For public pools that are constructed with a peristaltic pump (such as a Stenner pump), sodium hypochlorite, or liquid bleach is used. This chlorine product does not contain CYA. Calcium hypochlorite and lithium hypochlorite also do not contain CYA.
For pools that are sanitized with calcium hypochlorite, lithium hypochlorite, and sodium hypochlorite, service techs need to hand feed granular CYA into the pool water to cause the 30-50 ppm recommended CYA level.
Because there are no minimum CYA requirements in public pools or spas, most pool techs do not think to hand feed granular CYA into the water.
Subsequently, the pool water will not have any cyanuric acid and will result in more chlorine demand. This in turn creates a risk of recreational water illness outbreaks when levels of disinfectant drop below required minimum levels.
Often when I tested pool water, there was no CYA level at all. These public pools were fed by sodium hypochlorite peristaltic pumps and the pool service techs were unaware that they should hand feed some granular CYA into the water to help protect the chlorine.
A few years back there was a draft rule of Chapter 64E-9 of the Florida Administrative Code (FAC), that would have required the level of CYA to be maintained at 40 ppm or below for both public pools and spas.
This requirement was not included in the 2016 Florida rule update. Instead, the 2016 code added that it is recommended to keep CYA levels below 40 ppm on a public pool.
This maximum level of CYA was already required in public spas.
In conclusion, pool techs need to know the following: • CYA is necessary to properly maintain pools and spas.
• Pool techs will have difficulty maintaining pools and spas with either high or low levels of CYA.
• Both Trichlor and Dichlor contain CYA.
• Constantly using Trichlor and/or Dichlor will increase CYA levels.
• Service techs should regularly check CYA levels to maintain 30-50 ppm.
• It may be necessary to periodically drain pools and spas to maintain the recommended CYA level.
• Pool techs should educate pool owners and HOA members to advise them of the importance of proper CYA levels.
Five gallon bucket with drilled holes with trichlor tablets in collector tank
Peristaltic pump-Stenner pump setup