How to Maintain a Hot Tub Without Chemicals

Hot tubs are an excellent way to relax with your family, friends or even by yourself after a long tiring day. However, the limitation of a hot tub is that you can’t keep it clean and sanitized without adding chemicals such as chlorine, bromine, etc., which can irritate your skin and eyes.

Or can you actually maintain a hot tub without using chemicals?

Increasingly, people are looking for healthier and natural alternatives that can keep the water of the hot tub clean for a chemical-free experience.

While most methods require some type of chemical use, there are several systems that can help to reduce the use of harmful chemicals.

In this article, we’ll look at how you can reduce the use of harsh hot tub chemicals and still enjoy your hot tub in a natural and environmentally friendly way.

how to maintain a hot tub without chemicals

Natural Hot Tub Treatment Alternatives

There are several natural treatment alternatives that you can use for your hot tub, which can help to reduce the amount of chlorine usage or use of any other chemicals to keep it clean.

UV (Ultraviolet) Lights

Using ultraviolet lights is a great way to sanitize your hot tub without using chemicals like chlorine. The UV system works by deactivating the viruses and bacteria in the water through radiation when the water is passed through a filtration system and a tube containing UV lights.

While UV treatment helps to remove contaminants from the water, it is not a standalone solution and you may need to shock the water to maintain the clarity of the water.

Enzyme-Based Treatment

Enzyme-based treatment is a good natural alternative to treat your hot tub water. Usually, these products are food grade and help to digest the human skin fragments, body oils and other organic wastes that can be a breeding ground for pathogens and germs.

It also prevents the filter of the tub from getting clogged and the build-up of unpleasant foul odors.

While you may still need to use shock and sanitize to effectively clean the hot tub, enzyme-based treatment can help to reduce the number of chemicals needed to maintain the water.

Mineral Ionization

This process makes use of copper and silver ions to keep the hot tub water clean. When the minerals are ionized by the water, they form ions that are positively charged that are released into the water.

The ions are ingested by the pathogens in the water and are either killed, sensitized or made weaker so that they can be destroyed by other methods.

While mineral ionization helps to control the bacteria and algae, it does not work effectively on its own and you may need to use some other oxidizer like chlorine or bromine granules to treat the other contaminants and sanitize the water effectively.

Salt-Based Systems

While salt-based systems do not make use of chlorine and bromine; however, the process is not completely chlorine-free. In the end, the electrolyzing process of the salt does produce chlorine.

So, your goal of maintaining a completely environmentally friendly hot tub without using chemicals may not be met.


Ozone is an excellent oxidizer, as well as a sanitizer that helps to break down the organic contaminants in your hot tub and also eliminates most of the bacteria present in the water.

Ozone is produced by an ozonator when electricity discharge passes through the air or when UV light is shined in the air.

The process produces some stable oxygen, which then reacts with the electric discharge or UV light and produces ozone, which is less stable than oxygen. The ozone-enriched air is then passed into the hot tub and helps to oxidize the bacteria, as well as other contaminants, thus sanitizing the water.

While corona discharge ozonators generate more ozone; however, they do not tolerate high humidity. The air must be dried to ensure that the ozonator works properly, which makes these types of ozonators quite expensive.

UV-type ozonators are most commonly used for hot tubs at homes.

However, ozone disperses very quickly and there is no way to keep a reserve of the ozone. Also, there is no way to measure the amount of ozone produced.

Ozone may not be effective against some types of bacteria and pathogens and you may still require to use some chlorine or bromine, although in very small quantities.

Non-Chlorine Shock

Shocking your hot tub essentially is the process by which the organic compounds present in the water responsible for unpleasant odors and causing the water to become cloudy are broken down.

Shocking helps to oxidize the contaminants in the water and releases them in the form of a gas, eliminating the pathogens and algae, reducing the need for chemicals and also helping to enhance the life of the equipment.

It is recommended to shock your hot tub once in 7 to 10 days to keep the water clean; however, the frequency may depend on your size of the hot tub, hot tub usage, type of water, the weather in the area you live in, humidity levels and other factors.

There are 2 types of shock treatments commonly used—non-chlorine shock and dichlor shock.

  • Non-Chlorine Shock: This makes use of MPS (monopersulfate), an oxygen-based shock for regular maintenance of the hot tub.
  • Dichlor Shock: This uses sodium dichlor, which is a form of chlorine, which acts as a shock, as well as a sanitizer. A dichlor shock is usually recommended when the hot tub is refilled, after which it is best to go with the non-chlorine shock option.

Tips to Keep Your Hot Tub Water Clean without Chemicals

Here are some tips on how you can keep the water in your hot tub clean without using chemicals or by reducing their use.

Drain the Hot Tub Often

It is recommended that you drain your hot tub once every 4 to 6 months and if you’re not using any chlorine, then you must drain the water more often, i.e., every 2 to 3 months.

When draining the hot tub, make sure that you use a product that helps to remove build-up in the pipes, jets, hoses or other crevices of the hot tub.

Clean the Water Filters Frequently

To ensure that the water filters in your hot tub work efficiently, make sure to clean them regularly. You can do this by making use of chemicals and brushes specially designed to clean the filters.

Alternatively, you can simply run the filters under a cold-water faucet or put them into the dishwasher without a detergent.

Depending on the size of the hot tub and frequency of use, it is a good idea to replace the water filters frequently.

If you are treating your hot tub using a chlorine or bromine treatment, then the filters can be replaced once in 1 or 2 years; however, if the hot tub is a chlorine-free one, then it is recommended that you change the filter more frequently, every 6 to 12 months.

Run the Pump Longer

Typically, a hot tub has a pump that helps to circulate the hot water and sanitizer, which prevents the water from stagnating and becoming a breeding ground for bacteria, mosquitoes, algae, etc.

So, it is very important to run the pump of the hot tub for 8 hours at least or according to the manufacturer’s instructions. Keeping the water circulating can also help to reduce the number of chemicals needed to maintain the water.

Always Shower before Getting In

You must always have a shower with water and soap every time before getting into your hot tub. This helps to reduce the body oils, make-up, hair products and other personal products like perfume, deodorant, hair spray, gel, etc. getting into the water and dirtying it.

This is an effective way to reduce the use of chemicals and the amount of sanitizer needed to keep the hot tub clean.

Keep Your Hot Tub Covered

To keep your hot tub clean and well maintained, it is a good idea to keep it covered when it is not in use. This will help to prevent insects, dust, dirt and debris from getting into the water.

Covering the hot tub also helps to prolong the effectiveness of the sanitizer and reduces the chemicals required to maintain the water. This is especially important if you have a chemical-free hot tub.

Maintain the Right pH Balance

Irrespective of the sanitation method you’re using for your hot tub, it is very important to maintain the hardness of the water and the pH level of the water at the appropriate levels because if the levels are not right, this will reduce the effectiveness of the sanitizers in keeping the water clean.

The recommended pH levels are between 7.2 and 7.5, the hardness of the water must be between 180 ppm to 220 ppm and the alkalinity around 80 ppm to 120 ppm.

Test the water in your hot tub using reagents or test strips twice a week at least and add the chemicals required to keep the water balanced.

Parting Thoughts

In conclusion, while it may not be completely possible to eliminate chemical use in hot tubs, there are plenty of other natural alternatives that are effective, while helping to reduce the use of chemicals significantly.

We hope that after reading our article, you’re able to find the best way to maintain your hot tub without the use of chemicals.

michael keenan author

Author - Michael Keenan

I'm Michael Keenan the owner and creator of the Outdoor Care Guide. I'm a trained horticulturist with over 30 years experience in pool care, plant care and landscape care! Seemed like a good idea to share - I think I can make your life easier and save you some time and money!