How to Get Rid of Foam in a Hot Tub: Simple Steps to Follow

Michael Keenan


Hot Tub Troubleshooting

Hot tubs should be a place for relaxation, but when the water starts to foam up it can become a hazard. Foaming in your hot tub could be caused by extra surfactants in the water, an issue with water chemistry, or contaminants.

In this guide, you’ll learn how to get rid of foam in a hot tub and prevent it from happening again. We’ll start by testing the water and draining it out before cleaning all surfaces with vinegar or baking soda.

You’ll also learn about flushing pipes with cleaner and refilling and balancing your spa water. There are special chemicals you can buy if the foaming isn’t too bad.

Finally, I’ll cover ways to prevent foaming such as vacuuming debris regularly and adding calcium hardness increaser if needed. Read on for more information!

get rid of foam in a hot tub

Quick Answer:

Foaming in hot tubs is caused by an issue with extra surfactants, contaminants, or water chemistry. To get rid of foam you should test the water, drain and clean the hot tub, flush and clean the pipes, and refill the tub with balanced water.

If the foam isn’t too bad, you can use a chemical treatment or mix vinegar and baking soda. You can also prevent foaming by vacuuming debris out of the hot tub regularly and applying shock treatments to your hot tub once a week.

Why Is Foam a Problem in a Hot Tub?

It is likely that the foam in your hot tub is a result of an issue with extra surfactants in the water or an issue with the water chemistry. Contaminants in the hot tub can also lead to the formation of such foam. See my guide on the causes of hot tub foam for much more detail.

In this sense, then, the foam could be a sign of impurities and poor water quality. When you step into a foamy hot tub, the foam could come in contact with your skin and result in itchiness and rashes. It could also become a health issue if there are bacteria or harmful gases that enter your body since they can lead to illnesses.

Apart from these, the foam simply looks bad in your hot tub, taking away from the pleasant experience usually associated with a hot tub.

Have you got a problem with hot tub scum? Check out my guide about that particular problem.

foam problems

How to Get Rid Of Foam In Your Hot Tub

The first thing is to act quickly – don’t wait until it gets really bad! If you only notice a slight build-up of foam on the surface of the water – you can skip to the next section and try adding a foam remover product.

If the problem is more severe or keeps happening you should go all in and get rid of the foam for good. Get rid of the foam in your hot tub using the following steps.

Test Your Water First

Start by using a water testing strip to figure out how unbalanced your water is. This will provide you with a clear idea of the pH level as well as the calcium levels in the water so that you can solve those issues if necessary.

Drain and Clean Your Hot Tub

Attach a pump or hose to the drainage valve present in your hot tub and drain the water out from the tub. Make sure you turn the power off. You should then work on carefully wiping and rinsing the surfaces of the tub with some vinegar or baking soda and warm water. There are professional cleaning products if you prefer.

Flush the Pipes With a Cleaner

The plumbing pipes in your hot tub might also require cleaning due to a potential build-up of contaminants. There’s no point cleaning the spa and then letting the clean water run through dirty pipes and filters!

Purchase a cleaner and mix it with some water and run it through the pipes using pressure. Check the filters and either clean them or replace them if you want to do a thorough job.

Refill and Balance Your Spa Water

Start refilling water into your tub from a clean source. Use a hose filter if you use a garden hose to fill your tub.

Test it once again and add your chemicals to re-establish the pH and calcium levels to prevent the foam from forming again. Make sure to let the hot tub pump run for a day and test your water before using it again.

Find out how often you should be changing the water in your hot tub in this guide.

What to Do If Foaming Is Not Too Bad

If the foaming isn’t too bad, you can buy a chemical that specifically works against foam and helps rebalance the water. However, this is only a temporary solution to the foaming. They will remove the foam but they don’t fix the problem causing the hot tub to foam.

While it is okay to use this during an urgent situation or if the foaming is not too bad, you will still need to opt for a more permanent solution later on.

You can also try mixing vinegar and baking soda for a more affordable and simpler solution. I have used this and it does a good job – saves money and is more environmentally friendly!

too much foam in water

Ways to Prevent Foaming in Your Hot Tub

It is essential to prevent foaming in your hot tub so that you can avoid having to drain your tub every time. You should do this by removing the very sources of the contamination leading to the foam. Here are some ways to do this:

  • If you have a larger group of people waiting to use the hot tub, have them rinse off properly by taking a quick shower before entering the hot tub. This will help remove shampoos, lotions, oils, and any remaining soap from their bodies.
  • You will need to clean the filters in your hot tub regularly with a filter-cleaning product or solution. Simply pour or spray such solutions on the filter, let them rest, and then wash them off based on the instructions on the product.
  • Low calcium levels in the water are a common cause of foam in hot tubs. Add a calcium hardness increaser if you find that the calcium levels have become lower than normal.

Final Thoughts

Foam in a hot tub is never ideal – not only does it look bad but it can also lead to skin irritation or even more serious health risks if left untreated. To keep yourself safe from harm while enjoying your hot tub time, make sure you follow some key steps.

If the foam in your hot tub or spa isn’t very bad, use a chemical foam remover or water balancer. But for more problematic foam, go all in and give your hot tub a full clean.

Follow this guide and get rid of foam in a hot tub like a pro – you’ll be able to enjoy worry-free soaks whenever you please!


How can I prevent foam buildup in my hot tub?

To prevent foam buildup in your hot tub, you should keep the pH levels balanced, clean your filter regularly, and use shock treatments weekly to kill bacteria or algae.

Is it dangerous to have foam in your hot tub?

Having too much foam in your hot tub can be dangerous because it may indicate that there is an imbalance of chemicals or high levels of bacteria present.

How often should you clean the filter of a hot tub to reduce foaming?

To reduce foaming in your hot tub filter you should clean it at least once every two weeks and after heavy usage days.

michael keenan author

Author - Michael Keenan

I'm Michael Keenan the owner and creator of the Outdoor Care Guide. I'm a trained horticulturist with over 30 years of experience in pool care, plant care, and landscape care! Seemed like a good idea to share - I think I can make your life easier and save you some time and money!