Switching From Chlorine To Bromine In Hot Tub?

You can switch from chlorine to bromine in your hot tub. It’s important to note that you cannot add chlorine in the water that has bromine and the other way around. You should not mix bromine and chlorine. Chlorine activates bromine in water, meaning that the bromine will take a very long time to dissipate completely.

Therefore, your only choice is draining the water with chlorine inside. Then, clean your hot tub thoroughly, including the filters. Finally, fill the hot tub with fresh water and add your bromine.

What is Better for Hot Tub, Bromine or Chlorine?

There’s no straightforward answer to which is better, bromine or chlorine. This is because the sanitizer of your choice depends on your usage, specific needs, and budget. Both chlorine and bromine are effective sanitizers for use in hot tubs. We cannot emphasize enough the importance of using sanitizers because they kill any germs that may spread diseases to the hot tub users.

To help you make a decision, you should understand how each of the two sanitizers works. Chlorine is the most popular sanitizer probably because it’s cheaper than bromine. However, chlorine is extremely sensitive to any changes in your pH levels to the point where it stops working after pH changes even for a bit.

Chlorine is also the best sanitizer if you want to give your water a fresh look, without causing any irritations to the skin and eyes. Chlorine also tends to make the water have a bad odor.  With chlorine, you also need to use stabilizers together with the chemical, and you need to add it frequently if you want to have optimal results.

On the other hand, bromine is easier to use and lasts longer than chlorine. Another advantage of bromine is that it eliminates bad odors from the water, and you don’t need any stabilizers when using bromine as a sanitizer.

Chlorine and bromine are both popular spa disinfectants, but they do their job differently. Let’s look at the advantages and disadvantages of each.

Maintenance [Chlorine vs Bromine]

Chlorine spas require much more active maintenance and attention than bromine spas. Without constant attention, chlorine spas are much more likely to become cloudy or green.

In addition, the pH of spas can often increase rapidly, and bromine is less exposed to these pH fluctuations. Chlorine, on the other hand, cannot handle large fluctuations as effectively as bromine and therefore requires frequent attention.

Effectiveness and Efficiency [Chlorine vs Bromine]

Chlorine works faster than bromine, but it also dissipates faster because it decomposes faster at high water temperatures. However, once all the chlorine is used up, it must be re-dosed frequently. On the other hand, bromine tablets take longer to dissolve, and once the active bromine has killed unwanted organisms, there is still dormant bromine salt left, which can always be reactivated to active bromine. This makes bromine an active disinfectant for a longer period of time.

Water Temperature [Chlorine vs Bromine]

The ideal point for chlorine is between 65 and 99 degrees. At about 100 degrees, it quickly turns into steam. Although bromine is less effective at temperatures below 75 degrees, it thrives in hot water environments, especially above 100 degrees.

Spas are, well, hot, small, and there are usually several people at a time relative to their size. It is said that “4 people bathing in a typical spa is equivalent to about 160 people in a backyard pool because of the chemical requirements”. These factors cause bathers to sweat more, resulting in increased amounts of sweat and oils and an increased need for disinfection. Bromine is more effective than chlorine in treating the build-up of these wastes in hot water.

Cost [Chlorine vs Bromine]

Many people choose chlorine because it is cheaper to start with. Although bromine may cost 20% or more than chlorine, it can stay in your water longer because it can be reactivated after killing all bacteria. This means that you will use less bromine in the long run and therefore pay less.

If you live in an area that receives a lot of sunshine year-round, the cost of sunscreen may also play a role in your decision. Chlorine can be protected from the sun if you add the right amount of stabilizer. Bromine is degraded more quickly by the sun, so you need to add more to compensate for UV degradation.

However, when bromine is degraded by UV radiation from the sun, it leaves behind a dormant bromine salt (sodium bromide) that can be reactivated by adding additional bromine or a chlorine-free shock to provide additional disinfection.

Personal Considerations [Chlorine vs Bromine]

Chlorine is the subject of many jokes and urban legends. Some people with sensitive skin may find chlorine more irritating than bromine. According to experts, bromine protects the eyes and skin better and has less odor than chlorine.

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Does Chlorine React with Bromine in a Hot Tub?

Yes, chlorine reacts with bromine, and if mixed, it can lead to a severe chemical reaction. If you want to switch one for the other, you need to deep-clean your hot tub to make sure no residue is left.

What Happens if you Mix Bromine and Chlorine?

To understand what would happen if you mix chlorine and bromine, let’s discuss the components of bromine.

Chlorine and bromide ions make up bromine. If bromine and chlorine are mixed, then bromide ion converts the chlorine into bromine.

Generally, it is not recommended to mix bromine and chlorine in a hot tub. While both chemicals are used to sanitize the water, they work in different ways and can have adverse effects when mixed together.

When bromine and chlorine are mixed together, they can form halogenated hydrocarbons, which can be harmful to your skin and eyes and can cause respiratory problems. Mixing bromine and chlorine can also lead to unstable pH levels in the hot tub, which can make the water uncomfortable to soak in.

To properly sanitize your hot tub, it is recommended to choose one sanitizer and stick with it. Either bromine or chlorine can be effective at keeping the water clean and safe to soak in, but mixing the two can cause problems. It is important to follow the manufacturer’s recommendations for sanitizing your hot tub to ensure the best results and the safest soak.

Advantages of Bromine Over Chlorine in a hot tub?

  1. Bromine remains effective at higher pH levels than chlorine.
  2. Bromine is more stable at higher temperatures than chlorine.
  3. Bromamines retain killing power, chloramines do not.
  4. Bromamines do not gas off the water surface, as chloramines do.
  5. Bromine can be reactivated or re-used by adding granular oxidizer (shock).

Advantages of Chlorine Over Bromine in a Hot Tub?

  1. Chlorine tabs are much cheaper than Bromine, almost half the cost.
  2. Chlorine can be protected from UV Rays with Stabilizer, Bromine cannot.
  3. Chlorine is a more powerful oxidizer than Bromine.
  4. Chlorine is both an oxidizer and a sanitizer, Bromine is only used as a sanitizer.

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Is Bromine in a Hot Tub Bad for you?

The discussion on whether bromine is dangerous to use in a hot tub never ends. At the same time, you cannot entirely forego the use of bromine or chlorine as a sanitizer because your spa could become messy. There are claims that bromine causes cancer, respiratory problems, and weakens the immune system. While all these could be true, what can you do to protect yourself?

The use of bromine floaters to disseminate the bromine granules in the water means you get into contact with the harsh chemicals every time you use your hot tub. Therefore, to avoid having respiratory problems and low immune systems, always use bromine in the right quantities. Read the instructions manual to understand what works for your spa. Of course, the size and amount of water in the hot tub determines the amount of bromine to use.

Another tip that can help you minimize the way bromine reacts with impurities is taking a shower before getting into the spa. By doing so, the bromine doesn’t have to work hard to kill any bacteria, thus releasing less bromide vapor likely to cause respiratory problems.

Is Bromine a Positive or Negative Ion?

Bromide ion forms neutral atom bromine, which is negatively charged. Ideally, bromine reacts by gaining an electron forming a negative bromide ion.

What is the Difference Between Bromine and Chlorine?

Chlorine dissolves quickly in water, whether used in the form of granules, tablets, or liquid. As the chlorine dissolves, it combines with ammonia and nitrogen compounds in water, forming chloramines. Compounds of chloramine are inactive and cannot effectively disinfect the water in your hot tub. Therefore, after some time, you need to administer shock treatment to break the chloramines down before adding fresh chlorine to the water.

Bromine, on the other hand, dissolves slowly into the water, meaning that a small amount can work for a long time. Bromine breaks down into bromamine compounds while sanitizing your spa. These compounds don’t break down easily and can reactivate to function for a more extended period. Bromine is also effective for use in a variety of temperatures and pH levels compared to chlorine.

Does Bromine Kill Algae?

Yes, bromine is a sanitizer that kills any bacteria, mold, algae, and other microorganisms present in the water.

Does Bromine Increase Alkalinity?

No, bromine doesn’t increase the alkalinity of water in a hot tub. Bromine has a pH of about 4, and using it will result in a lower pH and alkalinity of water over time. Therefore, you need to add a base to the water sanitized using bromine so that you can increase its alkalinity.

What Bromine Smells Like?

Bromine is naturally liquid and has a brownish color. Compared to chlorine, bromine has a less pungent smell. However, if you’re sensitive to smell, you can identify bromine to have a bleach-like odor.

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Emily Williams

Emily is a passionate Hot Tubs researcher who loves writing about all things Hot Tubs! She has years of experience and a knack for simplifying complex concepts, these articles are here to answer all your burning questions in a simple and easy to read style.
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