What Causes Hot Tub Foam and How to Get Rid of It

close up of foamy water in a hot tub

Ah, the hot tub, a haven of relaxation and bubbling bliss, but what happens when that relaxing oasis transforms into a foamy frenzy? Don’t worry, fellow soakers, those suds don’t mean the party’s over! Fortunately, it’s relatively easy to understand what causes the foam and how to eliminate the issue. Let’s dive into the bubbly abyss and discover the culprits behind hot tub foam so you can restore tranquility to your watery sanctuary.

Hot Tub Foam, Understanding the Causes and Solutions

Foam needs three things: air, water, and surfactants. Surfactants are molecules that love both water and oil, acting like tiny bridges between them. In your hot tub, these soapy characters can come from various sources, one of the most common is the residual soap, lotion, and oils on the skin of folks who enter the spa. Without properly rinsing off these substances first, they can accumulate in the water, get whipped up by the jets and create foam, so be sure to shower before hopping into your tub. 

Similarly, residual detergent on swimsuits or cleaning product residue can contribute to foam. Only use hot tub specific cleaning products and thoroughly rinse your spa after cleaning to remove any residue. Dead skin cells, leaves, and other organic debris can break down, releasing natural surfactants that also fuel the foamy frenzy, so be sure to keep your tub covered when not in use. Inadequate water circulation or a clogged or dirty filter prevent proper water filtration, and can lead to foam formation. Clean or replace the filters regularly, especially if you have hard water.

High levels of calcium in the water can contribute to foaming, and is common in areas with hard water. If levels are above the recommended range, use a calcium remover or install a water softener to minimize calcium buildup. Unbalanced pH levels or overzealous sanitization can lead to excessive foaming, turning your hot tub into a bubble bath gone wild. Be sure to regularly test and adjust the pH and alkalinity levels of your hot tub water to keep it clean and sanitary.

How to Adjust Alkalinity in a Hot Tub

By understanding the common causes of foam in hot tubs and implementing appropriate solutions, you can enjoy a foam-free and refreshing spa experience. Regular maintenance and proper water chemistry balance are key to keeping your tub water crystal clear and foam-free. Adjusting alkalinity in your hot tub is an important part of maintaining proper water balance and preventing issues such as pH fluctuations and scale buildup. 

Start by testing the alkalinity level of your hot tub water using a reliable test kit or test strips. Refer to the manufacturer’s guidelines or consult a professional to determine the ideal alkalinity range for your specific tub model. Generally, alkalinity levels should be maintained between 80 to 120 parts per million (ppm).

To Increase Alkalinity if the alkalinity level is too low, below the recommended range:

  • Use an alkalinity increaser or pH increaser product specifically designed for hot tubs.
  • Follow the manufacturer’s instructions on the product label for dosage recommendations based on your hot tub’s volume.
  • Add the alkalinity increaser to the hot tub water near the jets or skimmer while the circulation system is running to aid in distribution.
  • Allow the water to circulate for some time before retesting the alkalinity level.

To Decrease Alkalinity if the alkalinity level is too high (above the recommended range):

  • You can lower the alkalinity naturally by partially draining and refilling your hot tub with fresh water which dilutes the alkalinity. 
  • Alternatively, you can use a pH decreaser or alkalinity reducer product designed for hot tubs.
  • Follow the instructions provided on the product label for dosage recommendations.
  • Add the pH decreaser or alkalinity reducer to the hot tub water near the jets or skimmer while the circulation system is running.
  • Allow the water to circulate for some time before retesting the alkalinity level.

After adding alkalinity increaser or decreaser, let the water circulate for a few hours before retesting the alkalinity level. If needed, repeat the process until the desired range is achieved. Depending on how often you use your tub, remember to regularly (weekly or bi-weekly) monitor and adjust the alkalinity levels in your hot tub to maintain optimal water balance and ensure a comfortable and safe soaking experience. 

With a little diligence and care, your hot tub will remain the relaxing spa you intended it to be. Give us a call with questions at 970-879-4390 or contact us here