How To Fix Cloudy Hot Tub Water

One of the most common questions our hot tub accessories team is asked, is how do I fix cloudy hot tub water? Cloudy hot tub water is a common issue for spa owners. With regular use, hot tub water can quickly turn from being crystal clear to a hazy grey very quickly.

As a provider of the UK’s best hot tub chemicals, Aqua Spa Supplies understands that fixing cloudy hot tub water can be difficult; especially for first time spa owners. With this in mind, here’s our beginners guide to fixing cloudy hot tub water.

What is cloudy hot tub water?

To put it simply, cloudy hot tub water is water with grey or milky appearance. This is usually caused by suspended particles in the water that are too small to touch or get picked up by your filters. The particles consist of a variety of substances including

  • Insoluble matter

  • Organic debris

  • Cosmetics like lotions and moisturisers

  • Dead algae

Particles are usually introduced to the spa by the bather. As a result, these can be from different materials, including:

  • Environmental debris – Insoluble matter such as dust and dirt from the outside

  • Organic matter – this would come from the bather and can consist of different organic matter such as skin cells and body oils.

  • Man-made contamination – Again most likely introduced to the water from the bather, these could include cosmetics such as detergents, make-up, lotions and moisturisers. They have washed off the bather into the water.

  • Heavy usage and low sanitizer level.

How to fix cloudy hot tub water

Fixing your cloudy hot tub water has never been easier. With our helpful guide, Aqua Spa Supplies will outline the best hot tub chemicals to keep your water clean.

Empty and refill your hot tub

Have you tested your water chemistry? Firstly make sure your core levels are correct:-

  • Ph: 7.4 – 7.6

  • Total alkalinity: 100 – 150 ppm

  • Sanitizer: – Chlorine 3 – 5 ppm / Bromine 4 – 6 ppm

  • Having low sanitizer levels can cause cloudy water as there just isn’t enough ‘fuel in the tank’ to cope with the organic matter being introduced into the water.

Shock treatment

The best way to treat your cloudy hot tub water is to shock your hot tub water. Shocking your hot tub water will burn off the organic matter, turning it into a gas and removing it from the water. We recommend using applying a chlorine shock treatment such as Aqua Sparkle Rapid Shock for an effective treatment.

Alternatively, you can use a non chlorine shock treatment, such as the YourSpa Non-Chlorine Shock Treatment. This product will also help those on bromine to activate the bromine and help it work more effectively. Non chlorine shock treatments are usually a preferred treatment by hot tub. owners as you will be able to use the hot tub after. By using chlorine, you will need to wait until the level naturally reduces to a safe level.


Filters can also affect the cloudiness of your water. Your hot tub filter requires regular cleaning, a blocked filters mean that they aren’t doing their job properly, so make sure filters are rinsed regularly and treating with a filter cleaner periodically to remove oils and greases. New filters need fitting every 6 – 12 months.

How can I prevent getting cloudy water in my hot tub?

The best way to prevent your water from getting cloudy is to

  • Shower before using hot tub (don’t use any soap, just rinse off in the water)

  • Don’t wash swimming costumes in detergent. Just rinse them in warm water after use

  • Clean filters regularly

  • Make sure your water chemistry is correct

If you would like more information on the best hot tub chemicals to prevent cloudy water, get in touch with our hot tub accessories team today.