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Stabiliser (Cyanuric Acid) is known by many alias’s – Pool Sunscreen, Sunblock, UV Shield – just to name a few. It is chemically known as Cyanuric Acid. Its main purpose is to act as a shield for the chlorine against damaging UV rays.

UV(Ultra-Violet) rays are naturally occurring and, in most cases, come from the sun. These UV rays are a natural destroyer of chlorine and, when chlorine is unprotected, can potentially strip a pool of chlorine in a single day.

To protect the chlorine, we add the cyanuric acid to the water to act as a shield around the chlorine particles. Simply put, the cyanuric acid wraps around the chlorine. It does not completely protect it, more so prolonging its life and ability to kill bacteria. Eventually the UV will destroy the chlorine, but at a much slower rate than when unprotected. This makes stabiliser a necessary product throughout the Summer period.

Is there such a thing as too much stabiliser? Too much cyanuric acid present can cause a chemical lock. This in essence smothers the chemicals instead of shielding them, meaning the other chemicals cannot perform their jobs properly. That then leads to water potentially developing algae or other bacteria growths as the chlorine is unable to properly sanitise the pool. Often, frustration can grow from pool owners when this happens as the normal treatments for algae growth or other issues become ineffective, due to the chemical lock.

The best practice to avoid the potential of cyanuric acid invoked chemical lock in your pool is to monitor what chemicals are being added to the pool. Products like stabilised granular chlorine or pool chlorine tablets have an element of cyanuric acid in them –Trichlorisocyanurate or Dichlorisocyanurate. These are great products in moderation but can be the cause of excessive stabiliser levels if used all year round . Alternative chemicals such as liquid chlorine (Sodium based) or calcium based granular chlorine can be fantastic alternatives to controlling these levels.

Of course, we encourage most pool owners to have a level of cyanuric acid in their pools. We find the best way is to purchase the cyanuric acid as a separate product – whether labelled stabiliser, sunscreen, UV shield etc – Our Pool Magic Pool Stabiliser comes in 1,2 and 3kg options so you can always purchase the bag size that best suits your pool.

Pool Magic Pool Stabiliser is available in store and online.