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CYA and Chlorine

By November 8, 2022November 23rd, 2022Maintenance

Is CYA and Pool Stabilizer the Same Thing as Chlorinating the Pool?

There is nothing more thrilling than jumping into crystal-clear waters. To keep your swimming pool water clean of bacteria and translucent, you must keep track of and test the water regularly.

Unfortunately, balancing your swimming pool chemicals can be daunting. Your best bet at always enjoying pristine waters is to hire a pool maintenance crew who will take care of all your pool’s needs.

Besides checking the water’s alkalinity and pH, you must ensure that chlorine levels are adequate so that bacteria and viruses are kept at bay. Chlorine gets broken down by sunlight and slowly degrades. When chlorine levels drop, germs and bacteria multiply rapidly, making the waters of questionable quality.

The way to help protect chlorine from the sun’s UV rays is by adding Cyanuric Acid (CYA) to your water. CYA balances pool chemicals and maintains steady chlorine levels in the water. Thanks to CYA, your pool will stay safe longer for you and your family.

To know more about your pool’s water and how to keep it clean, here is our guide on pool stabilizers, chlorine, and CYA.

What Does Chlorine Do?

Chlorine is used in swimming pools to kill bacteria and algae. It works by reacting with water molecules to form hypochlorous acid (HClO). HClO then reacts with organic matter such as bacteria and algae to produce chloramines, which are more effective at killing these organisms than chlorine alone.

Pool water gets dirty from sweat, germs, dirt, dust, debris, bacteria, and germs. As you don’t want to swim in polluted water, adding chlorine makes your pool water safe for swimming because it exterminates all harmful organisms.

The most common way to introduce chlorine into a pool is via an automatic dispenser. The amount of chlorine added depends upon the size of the pool and the level of disinfection required. For example, larger pools require higher concentrations to ensure that all bacteria are killed.

What is CYA?

CYA Controls Microorganisms Directly

Cyanuric acid (CYA) is an oxidizing agent used to treat swimming pools to kill algae, bacteria, and other microorganisms. CYA is usually added to water at concentrations that should be adjusted based on the size of the pool and the amount of sunlight exposure.

The EPA has set standards for CYA. According to these guidelines, the maximum allowable concentration of CYA in drinking water is 0.05 mg/L. However, the agency notes that this level may not be sufficient to control algae growth. For this reason, it recommends adding additional amounts of CYA to swimming pools.

In addition to controlling algae, CYA can also be used to prevent the formation of disinfection byproducts (DBPs). These DBPs are formed when chlorine reacts with organic compounds found in pool water. When CYA is present, the chlorine will react more slowly, reducing the production of harmful chloramines.

CYA Stabilizes Chlorine

Besides killing microorganisms directly, CYA is a pool stabilizer or pool conditioner. It helps stabilize chlorine when the latter is exposed to sunlight.

Sunlight breaks down chlorine and degrades it. Research has shown that within 45 minutes of sunlight exposure, chlorine levels can get depleted by as much as 50%.

CYA acts as a sunscreen on chlorine. Much like putting sunscreen on your skin protects you from sunburns, CYA protects chlorine so that its levels remain steady for longer. This lets it sanitize the swimming pool water, otherwise you’d have to constantly top it up to maintain it at effective levels.

What Happens When There Is Too Little CYA?

When the CYA levels are too low, chlorine degrades fast.

Without enough chlorine, your swimming pool is not properly sanitized and you could see the development of harmful bacteria. In addition, algae will develop and turn the pool water cloudy or green when chlorine levels are too low. Besides looking ugly, this could present a health hazard.

The swimming pool water chemistry is a delicate balance, which means it’s tricky to manage the chemicals in your swimming pool. When one component gets out of sync, the rest of them also suffer.

When CYA is too low, chlorine gets unbalanced. This, in turn, influences the pH balance and the alkalinity of the water, meaning you must then raise or lower the pH levels of your pool.

Normal CYA levels should hover between 30 and 50 ppm. When there is too little CYA, you must increase its concentration in the water. You can top up the CYA, run the pump, and test the water after a few hours to check the new CYA levels.

What Happens When There Is Too Much CYA?

Too much CYA affects chlorine because it constrains its effectiveness. As a result, the pool won’t be sanitized adequately.

When there is too much CYA, you have to dilute the existing CYA in the water. You can let the water evaporate and top it up with new water. If it rains, nature has taken care of the problem and has diluted the CYA. Take a measurement to make sure the CYA levels are within the acceptable range.

In extreme cases, you may have to drain the swimming pool. As always, the best cure is prevention, which is why our experts at Waterside Poolscapes advise swimming pool owners to test the water weekly so that any discrepancy is dealt with quickly .

What’s the Best Balance of Chlorine to CYA?

Your chlorine levels should be 7.5% of CYA; this is the perfect ratio where chlorine and CYA are balanced.

Since CYA levels should be between 30 and 50 ppm, chlorine should be between 1 and 4 ppm. If you have a CYA reading of 40 ppm, for example, the chlorine should be 3 ppm. At that ratio, your swimming pool is at its optimal level.

Does CYA Evaporate?

Unlike other chemicals, CYA doesn’t evaporate. Once you have put in the right amount, you 

must check on a weekly basis. You will have to do very little top-up unless it rains a lot and the rainwater dilutes the CYA.Should I Put Extra CYA When I Put Chlorine?

That depends on the kind of chlorine you use. Stabilized chlorine contains CYA. When you use stabilized chlorine, you don’t have to add extra CYA, or the CYA levels will be too high.

If you use unstabilized chlorine, you have to top up the water with CYA to protect the chlorine from breaking down from sunlight.

Waterside Poolscapes Are Your Pool Maintenance Crew

If you feel that swimming pool maintenance, chlorine levels, and monitoring CYA take up too much of your time, call Waterside Poolscapes at 281-690-4810 and our pool maintenance crews will take care of your swimming pool. We have the equipment, tools, and expertise to give you peace of mind!