Many pool and spa owners think that the strong “chlorine smell” means the water is well sanitized. In reality, it’s quite the opposite. That odor — and the eye or skin irritation that often comes with it — usually means your water is out of balance. The culprits? Chloramines, and the lack of what’s called breakpoint chlorination.

🧪 What are chloramines?

When chlorine reacts with organic matter such as sweat, body oils, lotions, or urine, it forms chloramines — combined chlorine compounds.
Unlike free chlorine (which disinfects), chloramines are much less effective and cause the familiar “pool smell.”

They also:

• Irritate eyes and skin
• Corrode metal components
• Reduce the overall disinfection power of chlorine

So, that smell isn’t a sign of too much chlorine — it’s a sign that you don’t have enough active chlorine to break down contaminants.

⚡ What is breakpoint chlorination?

Breakpoint chlorination is the process of adding enough chlorine to completely oxidize and destroy chloramines.
When the right amount is reached, the unpleasant smell disappears and the water becomes clean, clear, and properly sanitized again.

As a rule of thumb:

• You need about 10 times the level of combined chlorine to reach breakpoint.
• This is often achieved through a chlorine shock treatment.

💧 How to avoid chloramine buildup

1. Maintain proper free chlorine levels (usually 1–3 ppm for pools, 3–5 ppm for spas).
2. Shock your pool or spa regularly, especially after heavy use or warm weather.
3. Keep pH between 7.2 and 7.6 to optimize chlorine efficiency.
4. Ensure good filtration and circulation to prevent stagnant areas where chloramines can form.

📲 How iopool helps

The EcO connected water analyzer continuously monitors your chlorine and pH levels, so you know when to act before problems appear.
With the iopool app, you’ll get tailored recommendations — including when to perform a shock or adjust your chemical balance.

✅ Conclusion

That “chlorine smell” isn’t what it seems — it’s a red flag that your water needs attention.
By understanding chloramines and breakpoint chlorination, you can keep your pool or spa clean, balanced, and comfortable all season long.
With EcO, maintaining that perfect balance is simple and worry-free.