---
title: "What Is Cyanuric acid? Pool Glossary | Marina Pool Services"
description: "Cyanuric acid, also called CYA, stabilizer, or conditioner, shields chlorine from sunlight. Plain-English pool glossary from Marina Pool Services in Grapevine..."
url: https://marinapool.multisites.ai/glossary/cyanuric-acid
publisher: Marina Pool Services
phone: +1-817-896-1120
quote: https://marinapool.multisites.ai/contact
---

Water chemistry

# Cyanuric acid

Cyanuric acid, also called CYA, stabilizer, or conditioner, shields chlorine from sunlight.

Without cyanuric acid, strong Texas sun can burn most of your chlorine away in a few hours. A modest amount protects it. Too much does the opposite and makes chlorine slow, a problem called [chlorine lock](https://marinapool.multisites.ai/glossary/chlorine-lock).

CYA does not evaporate and does not get used up. Tablets and [dichlor](https://marinapool.multisites.ai/glossary/dichlor) keep adding it. CDC's guidance for pools using stabilized chlorine calls for a higher minimum chlorine level. The only way to lower high CYA is to replace water, so test it every month or two and plan a [partial drain](https://marinapool.multisites.ai/glossary/partial-drain-and-refill) if it is high.

[Marina can helpPool Maintenance Services](https://marinapool.multisites.ai/our-services/pool-maintenance-services)

## Related terms

-   [Stabilizer](https://marinapool.multisites.ai/glossary/stabilizer)
-   [Chlorine lock](https://marinapool.multisites.ai/glossary/chlorine-lock)
-   [Trichlor](https://marinapool.multisites.ai/glossary/trichlor)
-   [Partial drain and refill](https://marinapool.multisites.ai/glossary/partial-drain-and-refill)

## Sources

1.  [CDC Healthy Swimming: Operating and Managing Public Pools, Hot Tubs and Splash Pads](https://www.cdc.gov/healthy-swimming/toolkit/operating-public-pools-hot-tubs-and-splash-pads.html)

## Need a hand with your pool?

Call or text and tell us what your pool needs. Estimates are free for qualifying services, and same-day estimates are possible when the schedule allows.

[Call (817) 896-1120](tel:+1-817-896-1120)[Get a quote](https://marinapool.multisites.ai/contact)

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