Cyanuric Acid Testing

What is cyanuric acid?

Cyanuric acid (CNOH)3 is commonly referred to as a chlorine stabiliser. Chlorine is degraded by UV light, but the presence of cyanuric acid will protect the chlorine in the water from degradation and allow continued disinfection of the water. Cyanuric acid must be monitored if it is used in a pool to ensure that effective disinfection can occur.

Cyanuric acid is available as a solid or a liquid, but most commonly it is dosed as part of a stabilised chlorine chemical such as dichlor or trichlor.

Cyanuric acid in pools and spas

Cyanuric acid, commonly referred to as chlorine stabiliser, is often used in outdoor pools and spas to stabilise chlorine levels. Without cyanuric acid present, chlorine is more quickly degraded by UV light. Cyanuric acid levels should be tested weekly and should be below 200 mg/L. Many authorities suggest levels between 25 and 50 mg/L for maximum effectiveness.

Testing for cyanuric acid in water

Photometers are a well-known test method for testing and measuring cyanuric acid. The Pooltest 10 Photometer covers the 10 major tests needed for professional pool and spa management. Up to 500 data sets can be stored for full traceability of results. Utilise Bluetooth® to connect your devices and manage data via the Aqua Pal App and Palintest Portal. View our full range of photometers here.

Cyanuric Acid Testing icon

(CNOH)3  / CYA

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