Can You Run a Hot Tub Without Chemicals?

The thought of adding chemicals to the water you want to bathe in is enough to scare you and sometimes enough to make you wonder if you can use a hot tub without chemicals. Here is what I figured out from my hot tub.

You can run a hot tub without chemicals but only as a temporary provision. You should not run a hot tub without chemicals more than twice because that puts you at risk of bathing in fungi and bacteria-infested waters.

This post digs into the details of everything you need to know about adding hot tub chemicals into your hot tub, including natural alternatives that you can use instead of hot tub chemicals. So let’s get on with it.

How Long Will a Hot Tub Last Without Chemicals?

Hot tubs would last between 3 and 5 days without being used with any spa chemicals because the spa water will be at risk of scum build-up and bacteria infestation. On average, hot tubs last about 4 days if the spa is used without any chemicals.

You can use a hot tub without chemicals only temporary. But how long is that? You can run a hot tub without chemicals for 3-5 days. Sometimes less than that.

If the hot tub is used constantly by a large number of people, then it will not even last up to 3 days. What matters is how much you use the hot tub without the needed chemicals.

Germs that affect your hot tub as bacteria and fungi thrive in temperatures between 77degrees Fahrenheit (25 degrees Celsius) and 104 degrees Fahrenheit (40 degrees Celsius).

The hot tub is usually run with a water temperature between 95 degrees Fahrenheit and 104 degrees Fahrenheit. This means your hot tub is constantly being run at a temperature that allows fungi and bacteria to thrive. Without the needed chemicals, your hot tub is at risk of attack.

The hot tub is also affected by hot tub scum. Hot tub scum is the accumulated contaminants that build up in the water and these contaminants come in different ways.

The body care products, sweat, and skin cells that fall from your body into the water accumulate to form hot tub scum. Without the needed chemicals in the water, the hot tub can be plagued by a nasty case of hot tub scum.

If you run your hot tub without the needed chemicals, scum and germs will accumulate inside the hot tub water and after a few days, the spa will become unusable.

Does It Hurt the Hot Tub if You Don’t Use Chemicals?

Yes, it hurts the hot tub if you don’t use chemicals in it. But, the lack of chemicals doesn’t hurt the hot tub immediately. The lack of chemicals only starts to hurt the hot tub after a few days of consistent usage without chemicals.

Does it hurt the hot tub if you don't use chemicals?

When you run your hot tub without chemicals, the hot tub isn’t damaged or hurt from that singular action. The hot tub starts to get hurt when contaminants grow in the water due to the absence of hot tub chemicals. It’s the activities and presence of these contaminants in the water that hurt the hot tub over time.

The absence of chemicals in the water only allows the contaminants to form and grow in the water. Lack of chemicals doesn’t damage your hot tub on its own.

It’s a kind of cycle. If you don’t add hot tub chemicals to the hot tub, scum and germs will roam free in the water. The scum and germs will after a while start to hurt your hot tub.

The filters can get clogged and worn out. The hot tub shell, heater, and circulation pump will also suffer from scale build-up. The water in the hot tub will become very dirty and cloudy.

This can cause staining on the shell of the hot tub. The accumulation of scum can also drop the pH level of the water and cause etching. So much can hurt your hot tub and it all starts with the lack of chemicals in the water, so always add the needed chemicals to prevent damage to the hot tub in the long run.

Related Read: Are Pool Chemicals The Same As Spa Chemicals?

Do I Have to Clean My Hot Tub More Often if I Don’t Use Chemicals?

Yes, you will need to clean your hot tub more often if you don’t use chemicals in it because scum will quickly accumulate in the water. If your hot tub is being run without chemicals, the dirt and germs that get into the water wouldn’t be destroyed. This will quickly lead to an accumulation of hot tub scum and grime. This means you will need to clean your hot tub more frequently than usual because it is being quickly affected by contaminants.

Do you need to clean the hot tub more often if you don't add chemicals? Yes, the only reason people add chemicals is to let the chemicals clean the water so they don't have to.

Without chemicals, you will need to clean your hot tub at least twice a week under regular usage. Cleaning a hot tub isn’t the easiest of tasks and it’s certainly not a task you want to take on twice every week. It is stressful and time-consuming but if you don’t use chemicals in your hot tub, you would need to take on this task much more often.

The chemicals you add to the hot tub helps to limit the times you will need to clean your hot tub. The chemicals break down scum and stop them from growing inside the hot tub.

Under regular usage and with the right chemicals added in the water, you would need to maintain a light cleaning routine of the hot tub every week or every two weeks. Then you will need to drain the water every 3 to 4 months.

If you use the hot tub without chemicals, you will need to clean the hot tub at least 2 to 3 times a week, and you will need to drain the spa every week. This will put a lot of stress on your hot tub over time.

Related Read >>> How To Clean a Hot Tub Without Draining it?

Do I Need Hot Tub Chemicals if I Have a Self-cleaning Hot Tub?

You don’t need hot tub chemicals if you have a self-cleaning hot tub but you still need to shock the hot tub occasionally. Many of the hot tubs advertised as self-cleaning hot tubs don’t need hot tub chemicals. However, the hot tubs will still need to be shocked regularly to combat a buildup of dirt and germs in the water.

Self-cleaning hot tubs do a very good job of cleaning the hot tub. These hot tubs often have a device or method for cleaning the hot tub without the involvement of the owner.

Salt water hot tubs for instance are designed with a salt cell chlorinator that adds chlorine to the water regularly by converting hot tub salt to chlorine through a method called electrolysis.

Though the salt water hot tub cleans the hot tub regularly, the potency of the chlorine that is generated by the chlorinator cannot be compared with the potency of regular hot tub chlorine. This means after a while, the salt water hot tub will need to be shocked to complement the efforts of the salt cell chlorinator.

All hot tubs either self-cleaning or regular hot tub still need to be shocked regularly to give zero chance for scum and germs to accumulate in the water. So while self-cleaning hot tubs do not need hot tub chemicals to run them, you will still need to add hot tub shock to the water at certain times.

Many self-cleaning hot tub models will even encourage the user to shock the water in the spa regularly even though no chemical is needed to run the spa.

Why Do You Need Chemicals in a Hot Tub?

You need chemicals in a hot tub to destroy the contaminants that get into the water. Without chemicals, the hot tub will become prone to different attacks from germs and this can damage the hot tub over time. So in a broader view, you need chemicals in a hot tub to allow the hot tub to function properly.

Why do you need hot tub chemicals?

Virtually everything that goes into your hot tub is a contaminant and that includes you. Yes, you. When you soak in the bubbling hot water of your hot tub, you add different contaminants into the water. Your skin cells, body products, hair oils, and the sweat from your body are all contaminants in the water.

If you are also the type that likes to enjoy a snack in the spa, then you most likely add contaminants to the water every time you eat or drink in the spa. The food and drink can spill into the water to cause hot tub scum.

Asides from the contaminants that you add to the water, nature also adds a few contaminants into the water. Hot tubs are usually installed outdoors and under the elements.

If you are the type that leaves your hot tub uncovered, then several contaminants like leaves and blades of grass can be blown into the water by the wind. The effects of the sun on the water also allows algae to grow in the water.

The role of hot tub chemicals is to neutralize the effects of these contaminants and destroy them. When you add chemicals to the water, the chemicals prevent these contaminants from damaging the working parts of your hot tub like the filters and heating mechanism. Hot tub chemicals make the water safe for you to soak in.

Hot tub chemicals also help to adjust the properties of the water. For instance, if the alkaline level in your hot tub is high (or above 7.8 on the ph scale), you can add a high dose of chlorine sanitizer to the water to drop the alkaline levels to the needed range (or below 7.8 on the ph scale).

Related Read >>> Do Hot Tub Chemicals Expire?

Is There Any Natural Alternative to Hot Tub Chemicals?

There are a few natural alternatives to using hot tub chemicals in your hot tub. If you are a hot tub owner with sensitive skin or you don’t like the strong odor of chloramines in your hot tub, then you’ll be happy to know that there are a few natural substances that you can add to your hot tub water to clean them instead of chlorine or any other chemical. Here are some natural alternatives to hot tub chemicals.


Salt is one very common natural substance that can be used in a hot tub instead of hot tub chemicals. Salt is particularly used as a natural alternative to chlorine after all chlorine is a by-product of salt.

Some hot tubs known as salt water hot tubs use salt as the hot tub’s sanitizers. Salt water hot tubs have a device known as the salt cell chlorinator. The chlorinator converts salt to chlorine and then adds the chlorine into the water. This means you can use salt or hot tub salt as a natural alternative to hot tub chemicals.

This doesn’t mean you can just pour salt in your hot tub. Much goes into using salt as a sanitizer in your hot tub. Luckily, I cover everything you need to know about converting to a salt water hot tub in this recent article.

Ultraviolet Light

Ultraviolet light or UV light can also help rid your hot tub of germs. The water passes through a tube with UV light inside it. The light kills the germs and allows them to be trapped by the filtration system. This will help keep your water clean but a quality UV light filter can cost over $500.

Related Read >>> Why Does Hot Tub Smell Like Ammonia?


Biguanide is another natural alternative to hot tub chemicals. Biguanide helps to clean the water by binding the bacteria and scum in the water.

After binding the contaminants in the water, biguanide them wraps them and the contaminants become heavier so they can’t float in the water anymore. Instead, the contaminants drop down to the base of the hot tub and are picked up by the filtration system.

Biguanide is gentler than chlorine but it is also more expensive which is why it’s not a very common alternative.

Final Words

Overall, you can run a hot tub without hot tub chemicals but only for a limited time. If the hot tub is run constantly without chemicals, then it’s only a matter of time before your hot tub becomes the venue of the latest scum party. There are several chemicals and sanitizers to pick from. So make your choice and enjoy clean and healthy spa water.

So there you have it. If you liked this post, you should check out others like it on this website for more hot tub tips. Have a nice day.

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