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How Do I Raise Free Chlorine in my Hot Tub?

by Ron Schellenberg 07 Dec 2022 0 Comments

A question that is often asked is how to raise Free Chlorine in your hot tub.

Before providing an answer to that question, you need to understand the terms used on your typical test strip.

On a typical test strip, there is a reading for Total Chlorine and Free Chlorine.

Testing for chlorine

Total Chlorine is Free Chorine + Combined Chlorine

Free Chlorine is the chlorine that isn’t combined with anything. It’s free and available as an effective sanitizer.

Combined Chlorine is the chlorine that’s bonded or attached to the stuff it worked on. If your water is fighting something, your Free Chlorine will quickly turn to Combined Chlorine and your reading will be low. Combined Chlorine is also known as Chloramines.

If you’re experiencing a strong smell of chlorine, it’s likely that it’s the Combined Chlorine or Chloramines you’re smelling. What does that mean?! It means that the chlorine in your tub is “locked” and when that happens it does not sanitize efficiently. You will need to “shock” the water to break apart the chloramines and purify the water.

So, to answer the question, if your Total Chlorine is high but Free Chlorine is low, it is an indication that the hot tub requires a shock treatment. This can be done by adding your weekly dose of an oxidizer like Mineraluxe Oxygen, Dazzle Amaze or Spa Life Shock. Oxidizers will destroy chloramines and reduce waste by literally burning it off and will raise your Free Chlorine. When you add an oxidizer, make sure run your jets for 15-20 minutes with your hot tub lid open so that it can gas off. Following the treatment you are free to go in and enjoy!

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