🌫️ Musty-smelling water in your hot tub? Here’s how to fix it.

A fresh smell is a sign of clean and healthy hot tub water.
If your water suddenly smells musty or musty , it’s a sign of bacteria or organic debris . This blog post explains the source of the odor and how to solve the problem quickly and effectively.

🧐 Why does your hot tub water smell musty?

A musty smell is usually caused by:

• Too little active chlorine → bacteria and algae have free rein
• Wrong pH value → chlorine will not work properly
• Build-up of biofilm in pipes
• Clogged or dirty filters
• Poor or irregular maintenance

If this is not addressed quickly, the water can become cloudy and even cause skin irritation.

⚖️ Step 1: Measure the water values and correct them

Use test strips or a digital tester and check:

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

💡 Important: A correct pH value is crucial, because if the pH is incorrect, chlorine will hardly be effective , allowing bacteria to continue to live and cause odors.

🧪 Step 2: Perform shock treatment

If the water smells very musty or is cloudy:

1. Add an extra high dose of chlorine granules (according to the shock dosage on the packaging)
2. Let the pump run for at least 2 hours with the jets open
3. Keep the jacuzzi closed (covered) during this treatment
4. Retest the water after 12 hours and adjust pH or chlorine if necessary

A chlorine shock kills most of the bacteria that cause the odor.

💧 Step 3: Clean pipes and remove biofilm

The cause of the musty smell is often in the pipes :

• Use a pipe cleaner or a 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 well

This removes the built-up biofilm that traps the odor.

♻️ Step 4: Clean filters and maintain

• Rinse the filter thoroughly every week
• filter cleaner once a month
• Replace the filter every 3 to 6 months
• Maintain a maintenance schedule (check pH/chlorine, add AquaFinesse / AquaPerfect )

Regular maintenance prevents bacteria and odors from returning.