What is that smell in my hot tub?

"Bubbling Over" Newsletter Article - January 2006

There are lots of things that can make your water in your hot tub smell - even if you are diligent with your water chemistry. Let's talk about that smell. Sometimes hot tubs can smell musty, sometimes they can smell like rotten eggs, sometimes you just can't describe the smell.

Let's eliminate the obvious first. Chemical smells are the most prevalent and are most commonly complained about. While this is unavoidable you can try cutting down on Chlorine or Bromine by adding a mineral purifier, such as ThermoClear, and/or an ozonator, such as ThermOzone.

TIP: Let your spa air out for a minute before you get in. Turn on the jets and the blower system - if you have one - and let it run for a minute or two. This will allow trapped chlorine or bromine vapors to escape and should reduce the smell.

Next let's consider that musty smell that comes when you first open the cover of your spa. The musty smell is typically caused by algae, but it can also be bacterial. A couple of things contribute to this. A common cause is mold or mildew growth on the inside of the spa cover itself. These organisms grow here because they don't come in contact with the sanitizer. Condensation forms on the inside ceiling of the cover, then rains back down into the spa water, contaminating the spa water as well. The remedy is simple: clean the inside of your cover at least once a month.

Another reason could be that when you are in your hot tub you bring in lots of bacteria with you - no matter how clean you are. You eventually get out of the spa and close your cover. Although you leave the hot tub, your chemicals are working hard to kill the bacteria that you left in there. A process of oxidation occurs and vaporized bacteria basically have nowhere to go and stay in the air space between the water and the cover.

TIP: Keep the cover open for 5 - 10 minutes after you get out of the tub, so some of this smell can be eliminated.

If your water is cloudy and smelly, you may have bacteria in your water. Please call Customer Care at (800) 876-0158.

Happy Hot Tubbing!

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