7+ Reasons Why Your Hot Tub Might Be Foamy

Common causes of foamy hot tubs include alcohol, hygiene products, oils, soaps, pH imbalance, calcium hardness, and lack of cleaning.

why is my hot tub foamy

When we start our hot tub, we want to relax, hang out with friends, or maybe have a romantic evening. We don’t want the outdoor equivalent of a bubble bath. Unfortunately, there are many reasons why your hot tub could be producing excess foam.

Here, we’ll review 7 reasons why your hot tub is getting foamy because when you know what causes the foam, you will know how to prevent it.

But first, let’s address how foam forms.

Water, air, and surfactants combine, and you get foam. What are surfactants? They are substances that reduce the surface tension between liquids.

Hey hey – real quick! Don’t forget to subscribe to get our best content 🙂

This reduction in tension leads to the liquids spreading out. Surfactants include a litany of substances, explored below.

Disclosure: As an Amazon Associate, this site earns from qualifying purchases. Thank you!

Alcohol and Other Drinks

The contrast between a cold beer or cocktail and the hot water is tempting. However, besides the risk of broken glass entering the hot tub, alcohol (or sugary drinks) can make the tub foamy. 

There is also the risk of dehydration and over-relaxation (yes, it’s a thing). This can lead to a laundry list of problems, such as nausea, dizziness, and weakness. In some cases, people have lapsed into a coma or died. Stay safe, and keep the drinks away from the tub (ditto for saunas).

It’s not recommended you eat in your hot tub, either.

Hygiene Products

Almost every hygiene product you put on your body can make your hot tub foamy. Shampoo and Conditioner? Check. Deodorant? Check. Hairspray? Check. All of these chemicals are surfactants and can lead to foam. 

If you ever wondered why there are signs that ask you to take a shower before entering a hot tub, this is the reason. A quick rinse before getting in your hot tub can save you time and money later.

Oils or Lotions

If it’s creamy and you rub it on your skin, it’s probably a surfactant, and it can make foam. However, this isn’t limited to the oils you buy: your natural body oils also count.

The good news is this takes a while to happen, so forgetting to take a shower once before hopping in the tub won’t likely lead to instant foam.

However, if you often have multiple guests in your hot tub, these oils will accumulate much faster.


This category includes the soap you use on your body and the detergent used to wash your clothes. If there is excess laundry detergent on your bathing suit, this can leech off into the hot tub.

If you use your hot tub with your bathing or wetsuit on, you can add a scum digester to the water to help prevent foam.

Other Selfcare Products

Makeup is yet another surfactant that can cause foam. However, as long you keep your head above water (or wear waterproof makeup), it shouldn’t be too much of an issue.

If you didn’t expect to use a hot tub, it couldn’t hurt to spend a few minutes wiping off your makeup before you enjoy a soak.

pH Balance 

An imbalance of the water’s pH levels (high or low) can make foam. Worse, it can also lead to green or smell water.

An easy way to tell if the pH levels are off is if you see cloudy water. To confirm there is an imbalance, test the water with a chemical kit.

Calcium Hardness

Something you probably don’t think about often is how hard your water is. Calcium determines how hard your water is, and its presence in the water is crucial for keeping the water balanced.

Similar to the pH balance, you can tell if the calcium levels are off if the water is cloudy. Use hardness test strips to know for sure if the levels are off. If you do find the levels are too low, try adding a Calcium Hardness Booster,  calcium hypochlorite, or a calcium booster.

Further, the calcium levels can do more than cause foam: they can actively damage your hot tub. Your tub’s circulation system, pipes, pump, and filter. Calcium levels can also clog your pores and dry out your skin.

Cleaning Your Hot Tub

Another way to prevent foam in your hot tub (or Jacuzzi) is to start from scratch. Drain the water, clean the tub, and then refill it. Make sure you’re using non-abrasive cloths and good hot tub cleaning products.

You need to clean your hot tub regardless, so doing it the right way gives you a chance to reduce the odds you will have foam later.

Further, make sure to take the cover off your hot tub often. Doing so lets the tub breathe and allows oxygen to enter the tub.

What Do You Do If You Have Foam But Want to Use the Hot Tub Now?

Spa Cleaner & Hot Tub Cleaner Spray - Best Spa Surface Cleaner for Hot Tubs, Jacuzzi Cleaner & Hot Tub Surface Cleaner for Spa That Works as a Jacuzzi Cleaner & Tub Cleaner - MAV AquaDoc 16oz

If you’re pressed for time, a foam remover will rid your hot tub of foam for 24 hours. However, this is a temporary fix and does not address any of the underlying issues that cause foam.

FAQs about Foamy Hot Tubs

Here are the most common questions about hot tub maintenance.

How expensive is it to maintain a hot tub?

It should cost about $20 to maintain your hot tub.

Are the cleaning materials hard to find?

No, some of the cleaning materials you can use are already in your house, for example, vinegar.

How often should I drain my hot tub?

You should drain your hot tub every three to four months.

Is foam always bad for your hot tub?

No. Sometimes it’s just a result of TDS (Total Dissolved Solids) and products accumulating.

If I should be concerned about how hard my water is, should I use soft water?

No. Soft water is not good for your hot tub.

What pH level should my hot tub be?

Your hot tub’s pH level should be between 7.2 and 7.8.

Should I clean my hot tub with a specific tool?

Yes. Use a soft cloth and warm water. A rough sponge can damage the acrylic.

Besides the interior of the hot tub, is there anything else I should clean?

Yes. Clean your filters once a week.

More FAQs

How do you remove foam from water?

To remove foam from water, one can employ various methods. One approach is to spray the foam with water, similar to how firefighters use water to extinguish fires. Another option is to physically eliminate the foam by manual means. Additionally, chemicals can be added to the water to help eliminate the foam. Lastly, bioaugmentation can be utilized as a method to remove foam from water.

How much foam is normal in a hot tub?

The normal amount of foam in a hot tub is usually a small amount, especially if a bubble blower is being used. However, if there is a thicker layer of foam, simply draining and refilling the hot tub may not always solve the issue. Continue reading for some alternative suggestions on how to address and resolve foam problems in hot tubs and spas.

Does high pH cause foaming in hot tub?

High pH can cause foaming in a hot tub. A high pH level is more likely to directly lead to foam compared to a low pH. To prevent foaming from the spa pool jets, it is important to maintain pH levels between 7.2-7.8.

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

To naturally eliminate foam in your hot tub, you can create a solution using vinegar and baking soda in a 10:1 ratio. For a typical hot tub that holds 500 gallons, you would require a 5-gallon solution consisting of 90% vinegar and 10% baking soda.

Does low alkalinity cause foam?

Low alkalinity can cause foam in hot tub water, but it can be easily resolved. To eliminate foam caused by low alkalinity in your hot tub, you should adjust the alkalinity levels to a range of 80-150 ppm. This will effectively prevent foaming and act as a spa deformer.

Does low pH cause foam in hot tub?

Low pH levels can cause foam in a hot tub. When the pH levels are imbalanced, it can lead to a foamy spa experience. There are various factors that can cause fluctuations in pH levels, but maintaining a regular water treatment schedule is crucial in keeping the water clear, clean, and balanced.

What pH level makes a hot tub foam?

The pH level that can cause foaming in a hot tub is between 7.2 and 7.8. If you observe foam in your hot tub, it is advisable to lower the pH level by using a pH decreaser, such as Dry Acid. It is important to note that Muriatic Acid should never be used to balance the pH level in an acrylic hot tub.

Will shocking hot tub get rid of foam?

Rephrased answer: Shocking a hot tub can effectively eliminate foam by oxidizing the water and reactivating the chlorine or bromine present. This process aids in breaking down surfactants, effectively removing foam. If rebalancing the hot tub chemicals does not resolve the issue, shocking the hot tub can serve as an excellent next step in tackling the problem.

How do you reduce foam in water?

To reduce foam in water, one commonly employed method involves the addition of chemicals like glycols or alcohols, which often necessitate subsequent filtration to remove them.

Does chlorine get rid of foam?

Chlorine can effectively eliminate foam in a pool when it is shocked. If the foam persists, it is possible that insufficient calcium levels are causing the issue. To prevent foam from forming or increasing, pool owners can raise the calcium hardness of the water.

Will clarifier reduce foam in hot tub?

Clarifier will reduce foam in a hot tub by removing the foam particles and enabling the filter to capture them once more. To effectively use the clarifier, run the hot tub with the nozzles on for approximately an hour, and then remove and thoroughly clean the filters.

What causes excessive foam in a hot tub?

Excessive foam in a hot tub is caused by various substances, including drinks, soap, laundry detergent, deodorant, makeup, cosmetics, hair products, body lotions or oils, shampoo, and conditioners.

Can low pH cause foam in hot tub?

Low pH levels can cause foam in a hot tub. When the pH levels are imbalanced, it can lead to a foamy spa experience. Fluctuations in pH levels can be caused by various factors, and it is crucial to regularly maintain and treat the water to ensure it remains clear, clean, and balanced.

Does bromine cause foam in hot tub?

Bromine does not cause foam in hot tubs. However, if you are using traditional water care products such as chlorine or bromine, it is important to maintain the recommended hardness level. If no hardness has been added, the use of soft water can naturally result in larger bubbles and foam. Additionally, if you have not checked your pH level recently, this can also contribute to the formation of foam in your hot tub.

Similar Posts