Don’t Be Fooled: Foamy Hot Tubs Are No Joke

This is a 4-minute Read)

Did you hear about the practical joke the kids played on mom and dad by emptying a bottle of bubble bath in the hot tub and waiting for them to turn on the jets? Whether or not we just gave you an April Fools’ day idea, that has happened before. We at SilkBalance wanted to use this time of jokes and hoaxes to provide you with some facts about foam in your spa water and tips to prevent and fix it.

Foamy water occurs in spas and hot tubs for many reasons – naturally and accidentally. In many cases, it happens far too often for some hot tubbers. So don’t play the fool and get duped into believing foam is just a necessary evil of daily hot tubbing because it’s not. Once you understand some of the hidden “pranksters” that mess with your spa’s water clarity, you can spoil their fun and enjoy a stress-free soak in crystal clear and foam-free water.

Your spa is not supposed to resemble a bubble bath!


Eventually, the “Total Dissolved Solids” in your hot tub water are going to reach a level where that soot in the footwell reaches the water surface, thanks to your bubbling therapy jets, and converts to foam. Total Dissolved Solids (TDS) are a measure of combined tiny inorganic and organic substances that get introduced to your spa water. Everything, such as minerals, salts and metals to dead skin, oils and lotions, contribute to your spa’s TDS count. That’s why it’s important to keep your water levels within the acceptable ranges, especially sanitizers. Your pH should be 7.2 to 7.6, Total Alkalinity 80 to 120 ppm, Total Hardness 100 to 250 ppm, Salt Systems should read 3 to 5 ppm of Free Chlorine, traditional Chlorine 3 to 5 ppm or Bromine 4 to 6 ppm. It’s also important to note that most microscopic TDS get trapped in your filters, so rinse those often.

Once your spa water levels are within these acceptable recommended ranges, then a once weekly addition of SilkBalance liquid or SilkBalance Gems will help keep your water in the right ranges, crystal clear and full of … less foam.


As a hot tub owner, there are hidden things that change the chemistry in your spa water that you may not even think about. But if you did, you would have less foam to worry about. Foam also stems from health and beauty products, deodorants, soaps, beverages and just plain being a human.

Froth from beverages leads to hot tub foam. Adults and children alike are equally at fault here because alcohol and sugary kids drinks both encourage foam formation if they are spilled into the spa water.

Surfactants from health products are a big problem as well. Soap residue from your bathing suits or t-shirts, makeup, creams and lotions, hair products – including shampoo, conditioner, mousse and sprays all are perfect foam formers – especially if your hair is long.

Oils and dead skin cells from people also lead to TDS that we mentioned above. Once your TDS levels reach the point of saturation, foamy water leads to cloudy water because your sanitizers can’t keep up.

Tips to Help Prevent Excessive Hot Tub Foaming:

  • Designate a hot-tub only bathing suit that you can rinse after each use and wash less often than the rest of your laundry
  • We’ve also heard that some hot tubbers forego bathing suits altogether
  • Rinse off before entering your hot tub
  • Maintain your pH levels with a weekly dose of SilkBalance Gems or SilkBalance because excessive foaming can be a result of too high/low pH
  • Keep your calcium hardness levels within 100 to 250 ppm
  • Rinse your filters more often when you notice foam
  • Keep water levels within the proper ranges (see above) – especially sanitizers
  • Turn your filtration cycle up
  • Adding chemicals such as defoamers work the first or second time, but you can’t keep adding copious amounts of harsh chemicals to treat foam because your spa water will eventually reach the point where you need to drain and refill with fresh water. (When you do, make sure sure you rinse/vacuum/wipe the excess foam).
  • When the water is ready for a drain and refill, use Clean Start