It is a perfect Friday evening in Sioux Falls, SD. The kids are all out of the house participating in afterschool activities or playing at friends’ houses or doing anything else you’re not involved with. No one at work can bother you, because you switched your phone to airplane mode, intentionally drained its battery and sealed it in a lead-lined box. The sunset is glowing bright vermillion. No dour clouds are polluting the sky. You have good beverages in the fridge and ZZ Top’s Deguello on the stereo.


It’s spa time.

But as you’re walking toward that paradisiacal pool of bubbling 101 °F water, you notice something that instantly puts a sour spin on your otherwise idyllic eve. Foam. Your spa’s water is foamy, and it looks gross.

Don’t worry. That foam is harmless in the short term, so you can still enjoy your spa. Better yet, fixing foamy spa water is a straightforward process. But before you start creating the solution, it’s important to understand the source of the problem.


What Causes Foamy Spa Water?

Foam is just bubbles, and bubbles form on water when it (A) contains surface active agents (aka surfactants), and (B) is exposed to air. There are a number of different surfactants which could cause bubbles to form on water, including:

  • Detergent – A freshly washed swimsuit can still retain a significant amount of laundry detergent. Once residual detergent rises to the top of spa water, it can reduce its surface tension until bubbles easily form.
  • Sebum – Your skin produces a substance called sebum, which is an oily substance that protects your skin and hair from drying out. Hot water removes sebum from your skin – the reason why it’s better to wash your face with cold water when it’s dry, and also why spa water can quickly accumulate oil.
  • Low-quality chemicals – Sanitizer. Spa shock. pH increaser and decreaser. These are all necessary chemicals for any spa owner to have, but you may pay a price if you use cheap chemicals. Low-quality chemicals contain more filler substances that can act as surfactants!
  • Makeup and lotion – Almost all cosmetic products contain oil. If you get into your spa while you’re wearing facial cleanser, lotion, hair care products or makeup, you’re almost certainly introducing a significant number of surfactants to its water.
  • Aromatherapy products – You may feel that essential oils do wonders for your health and mood, but they don’t do any favors to spa water. If you’d like to breathe in some soothing scents while you’re relaxing in your spa, make sure they’re spa-approved oil-free products!
  • Total dissolved solids (TDS) – This is a catch-all term that covers essentially any inorganic and organic substances that can dissolve in water. The calcium and magnesium present in hard water are both TDS; so too are the sodium and chloride contained in your sweat. It is impossible to keep TDS out of spa water, which means foam is unavoidable without proper maintenance.


Surfactants aren’t the only factor which causes foamy water. If you fail to maintain the correct pH or alkalinity – or fail to regularly clean your spa’s filter – foam can begin to form. Likewise, allowing your spa water to become diluted with low-calcium rainwater can also cause foaming. With that in mind, let’s look at some solutions to your foam problem.


How Do You Get Rid of Foamy Spa Water?

It takes no more than four steps to restore your spa’s water to its ideal foam-free condition. Follow these steps in order. If steps one or two solve the problem, then it isn’t necessary to proceed to the next ones!

  1. Check the pH and alkalinity – Use test strips to see whether your spa water’s pH or alkalinity fall out of ideal range. If the water’s pH is lower than 7.2 or higher than 7.8, apply pH increaser or decreaser respectively. If the water’s alkalinity is lower than 80 or higher than 120, apply baking soda or pH decreaser respectively.
  2. Clean the filters – Your filters are ineffective at removing foam-inducing surfactants from the water once they become dirty. Remove your spa’s filters, soak them in an appropriate cleaning solution, and use a filter wand to rinse them out before putting them back in their respective places.
  3. Use an anti-foaming product – If foaming persists once your spa’s pH and alkalinity levels are both optimal and its filters are all clean, then you may apply an anti-foaming product. Alternatively, you may place a product like the ScumBug in the water. It is essentially a sponge that absorbs oil instead of water!
  4. Replace the water – Anti-foaming products aren’t permanent solutions to foamy water, unfortunately. When adjusting the pH, balancing the alkalinity and cleaning the filters doesn’t work, your only lasting solution is to run degreaser through your spa, drain it completely, clean its shell, and refill it with brand new water. Consider adding spa shock to the water weekly if you would like to take preemptive action against future foaming.


You deserve a completely foamless spa experience. If you need test strips or any of the high-quality chemicals required for regular spa maintenance, then you need only visit Paradise Patio, Pool & Spa at 1200 W 41st St in Sioux Falls, SD. If you would rather hire bona fide spa experts to make certain your spa’s water always remains foam-free and inviting, please contact us today!