Does your hot tub smell like chlorine? Here’s the real cause (and how to fix it)

Does your hot tub smell like chlorine? Here’s the real cause (and how to fix it)

Many people think a strong chlorine smell means there’s too much chlorine in the water.
In reality, it’s often the exact opposite : too little active chlorine and poor water balance .
This blog post explains the source of the smell and how to solve it.

🧐 Why does your hot tub smell like chlorine?

A strong chlorine smell is usually caused by:

• Chlorine that has bound to dirt and bacteria → this forms chloramines
• Too little free active chlorine in the water
• Incorrect pH value causing chlorine to not work properly
• Accumulation of biofilm in the pipes
• Dirty filters

Chloramines are what you smell—not the “fresh” chlorine itself.
They are less effective and irritate the eyes, skin, and respiratory tract.

⚖️ Step 1: Check the water values

First measure the most important values with test strips or a digital tester:

• pH value → should be between 7.2 and 7.6
  • Too low? Add pH +
  • Too high? Add pH
• Free chlorine → should be between 1 and 2 ppm
  • Too low? Add chlorine granules

💡 Please note: If the pH is incorrect, chlorine will not work properly and chloramines (the odor-causing agents) will be formed more quickly.

🧪 Step 2: Perform a chlorine shock

To remove the built up chloramines:

1. Add a high dose of chlorine granules (according to the shock dosage on the packaging)
2. Turn on all jets and the pump and let it circulate for at least 2 hours
3. Keep the cover closed for the treatment to be effective
4. Then let the water rest for 12 hours and test again

After a good shock, the strong chlorine smell usually disappears completely.

💧 Step 3: Clean pipes and remove biofilm

If the smell lingers, it is often due to biofilm in the pipes :

• Use a pipe cleaner or maintenance product such as AquaFinesse or AquaPerfect
• Let this circulate through the pipes according to the instructions.
• Then refresh the water completely and rinse the tub thoroughly

This removes the source of bacteria that cause chloramines.

♻️ Step 4: Clean filters and maintain

• Rinse the filter at least once a week
• Clean it deeply with a filter cleaner once a month
• Replace the filter every 3 to 6 months
• Maintain a maintenance schedule (check pH/chlorine, add AquaFinesse or AquaPerfect )

This prevents dirt from building up and chlorine from being used up too quickly.