When summer heat rolls in, keeping your pool sanitized becomes a little more challenging. That’s because sunlight—specifically UV rays—can quickly break down chlorine in your water. The solution? Cyanuric Acid (CYA), also known as the “sunscreen for chlorine.”
If you’ve never heard of it or haven’t checked your CYA levels lately, this blog will walk you through why this chemical matters, especially during peak summer months.

☀️ What is Cyanuric Acid?

Cyanuric Acid (CYA) is a Chlorine Stabilizer. It bonds to free chlorine molecules and shields them from being destroyed by sunlight. Without it, your chlorine can degrade by more than 50% in just a couple of hours on a hot day.

💡 Why It's Essential in Summer

During summer:

- Pools are exposed to more direct sunlight

- Swimmers bring in more organic contaminants (like sweat, body oils, and sunscreen)

- Chlorine is working harder than ever—and disappearing faster

CYA extends the life of your chlorine, making your sanitizing efforts more efficient and cost-effective.

🎯 Ideal Cyanuric Acid Levels

Too little CYA = your chlorine burns off quickly.
Too much CYA = your chlorine becomes less effective at killing bacteria and algae.

⚠️ Watch Out for Overstabilization

While CYA is helpful, more is not better. High CYA levels (above 100 ppm) can lead to chlorine lock, a condition where chlorine is present but not active. You’ll see cloudy water, algae growth, or poor sanitization—even though tests show chlorine is in the water.
If your levels are too high, the only way to reduce them is to dilute with fresh water or do a partial drain and refill.

🧪 How to Add and Maintain CYA

- Products: Sold as granules or pre-mixed stabilizer, or found in stabilized chlorine (like trichlor tablets or dichlor shock).

- Application: Always follow label instructions. Granular CYA should be dissolved slowly or added via skimmer sock to avoid damage to pool surfaces.

- Testing: Use a test strip or drop test kit. Many pool stores offer free in-store water testing.

-💡Pro Tip: If you're using stabilized chlorine (like trichlor tablets), you're already adding CYA—so monitor levels to avoid buildup over time.

🔄 Summary: Your Summer Sanitizer Sidekick

🧼 Final Thought

Cyanuric Acid might not be as well-known as chlorine or pH, but it’s a key player in your summer pool care routine. By managing your CYA levels properly, you’ll help your chlorine work smarter—not harder—keeping your water clear, safe, and swim-ready all season long.

✔️ Click here to order your 40# or 25# pail of chlorine stabilizer today.