Hot Tub Ozone Explained & How to Get the Most out of It

What exactly is Ozone? Ozone (O3) is a powerful oxidizer of germs, viruses, and bacteria in your hot tub water even bodily fluids like saliva and urine are neutralized. Ozone is formed with three atoms of oxygen that are bound together instead of the normal two. The Ozone molecules are injected into the water as a bubble during filter cycling, or in some cases through a separate circulation pump. The finer the ozone bubble the more effective it is. An ozone system can also help with lotions, soap, makeup, cologne, sunscreen, hair spray, and plumbing line biofilm. If that was not enough an ozone system helps remove minerals and total dissolved solids by chelating (clumping) them together so the filter can remove them from your water. The last big benefit ozone frees up combined chlorine and bromine, freeing them up to be reused

How do I get Ozone into my hot tub? Many hot tubs today come equipped with an Ozone System/Generator or have the option to add one. This is by far the most popular sanitizing system for today’s hot tubs. Ozone is not a replacement for other types of chemicals that kill unwanted bacteria in your hot tub water but is used in addition. This is because the ozone has a short life so works very slowly over time as it comes in contact with your water through the use of a pump. For this reason, it is not ideal for water sanitizing after the hot tub after it has been used, but instead maintaining clean water between uses without the need to add an additional sanitizer saving you money on those chemicals.

What chemicals should I use with Ozone? My preference is chlorine, as I think it works best when combined with an ozone system. If you really want to supercharge your ozone system, try adding a mineral stick like the nature2. It also kills bacteria in your water reducing even further your need for chlorine. This combination is perfect for anyone that does not want to be sitting in chlorinated water. The best way to run this system is by only putting chlorine in your spa when you are done using it for the day (generally a teaspoon per person) and then running a clean cycle, which is running the jet pump for 10 minutes. When the chlorine is mixed into the water, it works very fast to kill bacteria and other contaminants you may have left behind. This will clean the spa water right away and the chlorine will be gone the next day when you go to use your hot tub. The Ozone will take over from there and keep the water free of contaminants. Be sure to add a non-chlorine shock and test your water weekly. Adjust alkalinity, and pH as needed.


One of the biggest questions I get from customers is how to maintain the proper chlorine level when using ozone. The basic answer is you don\’t. If your test strip reads zero chlorine, everything is OK you don’t need to add chlorine. As discussed before it means the chlorine you have added has been used up. You should only need to chlorinate it after you have used it for the day and be ready for the next time you use it.

Another type of chemical you can use is Bromine. The drawback of this treatment is that it dissolves into the water slowly over a long period of time and is always there. Not only does this make the ozone system redundant, but it also means you will be soaking in bromine, which is a harsh chemical.

In review: Ozone generators are a great addition to your spa to keep the water clean and healthy, and it works even better when you add chlorine after each use. Don’t forget to run that clean cycle!

Keep on Swimming N Soaking!

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