Why do I have foam in my hot tub?

The most common causes of hot tub foaming

Foaming in hot tubs is one of the most common water care issues our customers come across and unfortunately, once you have it, it can be stubborn to completely remove. The most common causes of foam in hot tubs are detergents and cosmetic products being introduced into the water when in use. Showering before getting into your hot tub can help prevent foam forming by reducing the amount of foreign pollutants introduced to the water.

Some of the most common causes of hot tub foam are:

  • Hair products such as shampoos, hair gels and hair sprays
  • Deodorants and skin lotions
  • Makeup
  • Soap residue from your laundry
  • Cheap hot tub chemicals or excessive use of chemicals
  • Drinks
  • The build-up of total dissolved solids (TDS)

Hair products

Your hair will always contain residue from shampoo, conditioner, gel, hair spray and mouse which transfers to the hot tub water when your hair comes in to contact with it. If you have long hair we advise you to tie it up, away from the water.

Deodorant, body moisturisers and perfume

Everyday cosmetics on your skin can cause foam within a hot tub. Showering before heading to the hot tub is always the best option to remove these products from your body. Any fake tanning products are a big no go! The chemicals in your hot tub will remove the tan from your skin and turn your hot tub shell, pipe work and internal systems brown or green!

Washing powder

One of the most common errors people make is washing swimming costumes in the washing machine. Even if you do not put detergent in the machine for that wash, residue powder can be transferred to your costumes. Always wash your costumes in warm water, by hand in the sink to ensure that no soap is trapped inside the fibres that can later enter your hot tub. It’s good practice to have a separate bathing costume just for hot tub use that’s never washed with detergents.

Cheap chemicals or excessive chemical use

Cheap chemicals are often packed with fillers that dilute the chemical effectiveness and often cause foaming. Always check the chemical grade before making a purchase and buy chemicals from a trusted hot tub store. At Outdoor Living, we don’t sell any chemicals lower than grade 5 and we recommend you read the guidelines provided for chemical usage with your hot tub make and model.


Spilling drinks in your hot tub

Whilst most hot tub owners will have drinks in the hot tub at some point, it is essential you’re careful with them as spilling drinks in your Hot Tub can lead to foaming.

A great way to help prevent spills in the hot tub would be a Floating Spa Bar or a Spa Caddy Table. Both hot tub accessories will allow you to store your drinks reliably and avoid spillage.

High TDS (Total Dissolved Solids)

Total Dissolved Solids are minerals, salts and metals that are dissolved in water. When the level of TDS in your hot tub becomes too high the water will ‘die’ and the chemical balance will be extremely hard to maintain which can lead to foam forming.

How do I get rid of foam in my hot tub?


The first step in removing foam from your hot tub would be to test the water for a chemical imbalance. You should check the chlorine/bromine level of your hot tub water as well as the pH level. Using your normal chemicals to restore the balance may solve the issue, however you could try using a no foam product that clings to the pollutants in the water and sinks them to the bottom so they can be taken to the hot tub filter.

If the issue is related to TDS, the only solution is to replace the how tub water. This should be done every 3-4 months. You can also help this be cleaning your filter weekly and replacing your filter every 12 months.