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How to Reduce Chlorine in a Hot Tub


If you own a hot tub or you are considering purchasing a hot tub, it is important to understand how to maintain it so that it functions correctly, is hygienic, and that you don’t have too high levels of any of the chemicals used within it. Sometimes it is not even intentional that your hot tub contains too high a level of chlorine, but understanding hot tub chlorine levels will help you to have a more effective, soothing, and useful hot tub in your back garden.

What happens if a hot tub has too much chlorine in it?


If there is too much chlorine in your hot tub the first thing that you’ll notice is that you might suffer damage to the colour of your swimwear, or the cover you use for the hot tub will become faded. On top of the colour being damaged on anything that comes into contact with the water, there are other issues too.


Too much chlorine in a hot tub can be dangerous to you, your family and your friends too, especially those who have sensitive skin and some other health conditions. An example of this would be suffering with irritation of the eyes, skin rashes, and breathing problems in some cases.


When there is too much chlorine in the water, the excess will begin to evaporate and vaporise, creating a gas that will float just on the top of the surface of the water. If you inhale this, it can cause problems with your breathing and can inflame the airways. If you already suffer with breathing problems, you might find that these are exacerbated.


What can cause chlorine levels to be too high in your hot tub?


The biggest reason why your hot tub might have too high chlorine levels is that too much chlorine has been added into it by mistake. This could be that you accidentally added more than you realised, or that someone else had already added enough chlorine in the hot tub before you have, and you did not know so added more into the hot tub. Sometimes, the levels of chlorine in the hot tub may rise after shocking the water to activate sanitisers and kill bacteria.


How do I find out what the chlorine levels are in my hot tub?


It is important that you regularly check the levels of chlorine and other chemicals in your hot tub to ensure that there are not dangerous levels. You can test this by using test strips or a digital test kit. This gives the most accurate results. If you do this several times a week during the summer months, keep a record of each test result to ensure you can track the results over time and stay on top of the chlorine levels and adjust whenever necessary.


How much chlorine should be in my hot tub?


The ideal level of chlorine within a hot tub is 3ppm. Anything below 2ppm might mean that the hot tub is not sanitised to an acceptable level. You must be aware though that chlorine levels that are above 4ppm is too high and this might cause problems such as skin irritation. Dangerous levels of chlorine would be anything above 6ppm.


How can I lower chlorine levels in a hot tub?


There are a few ways in which you can lower the level of chlorine in your hot tub if you have discovered that it is too high. This includes:


Allowing chlorine to evaporate


In order to counteract the levels of chlorine you can leave the cover off the hot tub for a few days and allow the natural sunlight to break down the chlorine and evaporate it. During this time, you should not allow anyone to go into the hot tub until the levels are back to a safe figure.


Drain the hot tub


If you find that you need to reduce the chlorine levels by 1-2ppm, you can dilute the water in the hot tub by draining it and replacing it by fresh water. This drains both the water and the chemicals that are present. Adding fresh water will change the pH, calcium hardness levels, and alkalinity


Use chemicals to oxidise


Certain chemicals can be used to counteract chlorine in your hot tub, such as hydrogen peroxide, but you must be careful that you don’t exceed safe levels of other chemicals used in hot tubs and swimming pools.


Learning how to maintain and sanitise your hot tub is a fantastic way to enjoy a hot tub in your back garden. This can be achieved by understanding hot tub chlorine levels and how this can impact on the standard of your hot tub.