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What is Stabilizer?

Cyanuric Acid, or C³H³N³0³, belongs to the chemical family of Isocyanurates, and is used as a chlorine stabilizer.  It forms a weak bond with chlorine, and shields the molecule from degradation by the sun’s ultra-violet rays.

Cyanuric acid is abbreviated as CYA, and is commonly sold in granular form, and may be labeled as pool “stabilizer” or “sunscreen”.

Who should use Cyanuric Acid?

Outdoor swimming pools benefit the most from having a proper level of Cyanuric Acid in the pool water, by protecting the chlorine from rapid depletion by the sun.  Cyanuric Acid is considered a “stabilizer” as it stabilizes the chlorine molecule from solar degradation.

Indoor pools and spas or hot tubs need not use Cyanuric Acid, since the exposure to sun in both cases is usually very minimal.

What Level of Cyanuric Acid is Optimum?

Even very small amounts of Cyanuric Acid will help extend your chlorine in an outdoor pool.  CYA is measured in parts per million, and a reading of 40 – 80 ppm is considered optimum.

Experts agree that when Cyanuric Acid levels are too high, a phenomenon known as “Chlorine Lock” can occur, where your test kit will show no chlorine in the water, even though you have witnessed chlorine tablets dissolving, or have just shocked the pool.  Generally, this occurs when CYA levels climb close to 100 ppm.

Cyanuric Acid levels should be maintained above 35 ppm and below 80 ppm.  The higher your level of Cyanuric acid is, the less efficacy, or killing power your chlorine has.  As CYA levels approach 100 ppm, you will have superior protection from the sun, but your chlorine molecule becomes weaker due to the amount of CYA attachments or bonds being made.

A 2007 study showed that levels of Cyanuric acid above 50 ppm significantly diminished chlorine’s ability to kill bacteria.  Chlorine molecules that are “over-protected” by too much CYA can lead to excess chloramine formation, as nitogen and ammonia are easily able to attach themselves to these “slow and sluggish” chlorine molecules.

What is Stabilized Chlorine?

Certain types of chlorine products are labeled “Stabilized”, namely granular chlorines such as Trichlor and Dichlor.  These two products are in the family of isocyanurates, and put simply – they already have Cyanuric Acid in the mix.  When using products such as Trichlor or Dichlor granular chlorine or tablets, you can expect to add a small amount of Cyanuric Acid to the water.  Over time, adding these small amounts of CYA to your pool may cause your Cyanuric Acid level to rise too high.

In most cases, however, using Trichlor or Dichlor won’t cause your CYA level to climb very noticeably, especially if you replace water regularly through backwashing or splash out.

How do I Raise Cyanuric Acid Levels in my Pool? 

We recommend cleaning the filter first then mixing the required amount of stabilizer into a slurry in a bucket, then adding it slowly through the skimmer box with the pump running.  Let the pump run for a few hours after adding the stabilizer to help it dissolve.

Adding the correct amount of Cyanuric Acid is important, so that you don’t overshoot the mark.  Make sure that your CYA level is tested, and you know your pool size – to determine the correct amount of Cyanuric Acid to add to the pool.  If you have drained your pool and are refilling, you will likely be starting from zero, however – some water treatment facilities use Cyanuric acid in their process. Again, be sure to test your water first, and be careful to add the proper amount to the pool.

How do I Lower Cyanuric Acid levels in my Pool?

By dilution, which means to drain a portion of pool water and refill with water that has no, or very low levels of Cyanuric acid.  There is no chemical available that will remove Cyanuric acid, and it does not deplete on its own.  It will be reduced by dilution from rain, backwashing, splashout and lowering the water level.

How do I Test the Water for Cyanuric Acid?

If you are near our Pool Doctor store bring in a pool water sample during business hours, we can test it for you and let you how much, if any, you need.

Call into the Pool Doctor showroom 161 Old Pacific Highway, Oxenford to view our range of pool maintenance and cleaning products.  Or email us with your specific enquiry.