How to Get Rid of Foam From Your Hot Tub

We have all had foam or have at least heard of foam build-up in hot tubs. This pesky foam can become an extreme nuisance while relaxing in your spa. So what causes this build-up? To know why, and how to fix it, we must go  back to the basics.What Causes Foam?

Imagine yourself walking alongside an oceans beach, maybe you have noticed foam. sea foam is fundamentally the same as the foam in your hot tub, just with a slight difference in chemical composition.

Foam needs three thing to appear, water, air and surfactants. All of which we encounter in our everyday lives. For those who are not aware of what surfactants are, they are viscous molecules that reduce the surface tension of a liquid. This allows for substances like oil and water to easily mix. Your water, although looks crystal clear, is actually filled with various organic compounds- many of which are surfactants. Even with proper maintenance, your spa still contains these molecules. Which means that one little hick-up on your weekly maintenance, or not properly cleaning the water after a big use, you might end up with a frothy mess when you turn on your jets.

How do Surfactants Work?

Every surfactant varies from one another, although their structure is quite similar. They all have one end that attracts itself to water and one end that is not attracted to water. When you add air to the mix, surfactants organize themselves right on the boarder between water and air. This means it is easier for oil and water to mix. Surfactants, most commonly create a thin layer of water between themselves, this formation will push the water into a ball creating the bubble. The more surfactants in your water, the more build-up of bubbles you will get.

The conclusion, foam, and lots of it.

Three Most Common Surfactant Providers

1.Personal Hygiene Products

Any hygiene products are going to affect the chemistry of your water. Usually resulting in your sanitizing products working too hard for they work they do. Over time, these products will cause the formation of foam, as most products are stuffed with other surfactants.

2. Beverages

We all love to enjoy a nice drink while we relax in our spa, although keeping the drinks away from your spa is much more beneficial. These sugary drinks can lead to foaming in your spa. As enjoying as it is, the hassle of the clean-up is much worse.


Yes, even you will affect the chemistry of your spa. When we break down the components of the human body and what it produces, we are able to understand the affects that it can have on the water. We cannot eliminate the oils and dead skin that our bodies produce, that is why it is extremely important to keep up with sanitizing the water in our spas.

Just like personal hygiene products, over working your sanitizing chemicals will cause foam in your tub.

How to Get Rid of Hot Tub Foam

Getting rid of foam is actually easier than you might think. Before you try to do any corrective matters on your own, TEST YOUR WATER. A water test will help to see the chemical breakdown of spa’s water. Testing for pH, sanitizer, alkalinity, and total dissolved solids will help in better understanding why your spa is foaming. As well, we can establish what your water looks like after the foam is gone to help prevent these frothy matters from happening.

Other issues in your tub can cause foaming. A low calcium hardness level, among other things can cause foam in your tub. It is important to test these levels regularly to prevent corrosion, prevent foaming, and protect the finishes of your spa.

Sometimes, draining and refilling your tub is the easiest and best way to get rid of the pesky foam. As you are already having to drain your tub, it is best you give it a deep clean as well. Thoroughly cleaning your spa while it is drained will help prevent future foam.

Basic Steps to Drain Your Hot Tub

Use a line flushing product, as needed, according to the package directions. Remove all filters and chemically them depending on how dirty or replace them all together (if you’re unsure, replacing them is the safer option). Here are some links to a couple filter cleaners we recommend:

SpaGuard Filter Brite:

Mineraluxe Filter Revive:

Turn off the power to your spa disconnect any electrical, and trip the breaker. Then you can drain the water using a sump pump or the drain plug on your hot tub.

Basic Steps to Clean and Refill Your Hot Tub

Once your hot tub is entirely drained, wipe down the interior surface with a surface cleaner. Here are the links to a few we recommend:

Pool and Patio Cleanse:

Clean and Perfect:

Swirl Away 2:

Thoroughly rinse your tub, and ensure all traces of the cleaner are removed. Otherwise, the foam will come back! Place your filters back into the hot tub and refill your spa. We recommend using a hose filter attached to your garden hose to prevent chemical impurities.

after you have drained, cleaned and refilled your hot tub, test the water and add the chemicals it needs, allow it to circulate for at least a day. when the circulation is complete, test the water once more to ensure it is ready for soaking.

For Quick Fixes: Anti-Foam Chemicals

Sometimes we just need a quick fix, say you have a party coming up and you don’t have time for all the steps. You can buy a foam remover, this works almost instantly and can last for up to 24 hours. Although, this will not solve the root cause of your foam issue. You’ll still need to drain and refill to rid your hot tub of foam.

The best way to combat foam in a hot tub is to prevent it. Here are a few recommendations for your maintenance.

  1. Buy your chemicals from a trusted source, even if you are paying a little more.
  2. Maintain a regular maintenance schedule. This includes regular water testing and a drain and refill every 3-4 months.

Having foam in your hot tub might feel like a big pain, but correcting it can be fairly simple. Once you have a clean hot tub and fresh water, preventing foam in the future will be easy. Just remember to avoid adding things that make your sanitizer work overtime and keep a regular maintenance schedule.

Happy Swimming!


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