How to Lower Chlorine or Bromine Levels in a Hot Tub? (6 Steps)


Adding hot tub sanitizers like bromine and chlorine to the water in your hot tub is a crucial part of hot tub safety. These sanitizers help to keep the water in the hot tub safe and clean but they have to be added in the right amount.

Having too much chlorine or bromine in the hot tub will cause corrosion on the shell of the hot tub and it will also lead to skin irritation.

Though it’s unusual to have too much chlorine or bromine in the hot tub water, it’s still a possibility. So how can you lower the chlorine and bromine levels in a hot tub? Let’s find out.

Why is My Chlorine Level Always High?

The chlorine level in your hot tub is always high because the water pH is off balance, there is too much chlorine in the water, and the chlorine isn’t being used.

If you have always a high level of chlorine in your hot tub, you should check your pH levels first, that could be the reason.

Chlorine sanitizer needs to be added to the water in the right amount. If you add too much chlorine to your hot tub water continuously, it will alter the pH levels and cause a consistent level of high chlorine in the water.

Chlorine like many other hot tub sanitizers works best at low pH levels. When you add chlorine to the water, hypochlorous acid is released. This is a weak acid but it will lower the pH level in the water to allow the chlorine sanitizer to work better. The more chlorine you add to the water, the more the amount of hypochlorous acid in the water and the lower the pH level drops.

Since the water pH is very low, germs can’t grow in the water which means that you will constantly have active chlorine in the water with no germs or scum to destroy. So you end up with consistent levels of high chlorine in the water because the chlorine is not being used up.

Why is My Bromine Level Always High?

Why is My Bromine Level Always High?

Like every other hot tub chemical, bromine needs to be added to the water in the right amount. When you add bromine into the water, the chemical releases bromamines. Bromamines are the chemicals that clean the water.

Only that they don’t just clean the water, they also lower the pH levels of the water a bit to make it tough for germs to survive. The more bromine you add to the water, the more bromamines are released, and the lower the pH level drops.

So if you add too much bromine into the water, the pH level would be lowered below the recommended range and this will cause acidic water. Hot tub germs can’t survive in acidic water so there wouldn’t be any germs in the water. While this is a big plus, it is also a big concern. If there is no germ or scum in the acidic water, there is nothing that the bromine is fighting.

So you end up with too much bromine in your hot tub and no hot tub scum. This will quickly lower the pH level of the water and you will end up with a consistent level of high bromine level since the pH level is off and the bromine isn’t being used.

How to Lower Chlorine or Bromine Levels in the Hot Tub?

Having sanitizers like chlorine and bromine in the water is needed for hot tub safety. But you might have been careless with the dosage of these sanitizers or maybe you accidentally spilled too much into the water. That can cause a case of too much chlorine in the water.

So you will need to reduce it, but how do you go about that

1. Test the Water

The first thing to do if you suspect you have too much chlorine or bromine in the water is to test the water to be sure. You can take a sample of the water to a lab or a local pool store to have it professionally tested. You can also test the water by yourself by purchasing hot tub testing kits.

The water test will indicate how much active or free chlorine or bromine is still in the water. The ideal chlorine level for hot tub water is between 1 part per million (1 ppm) and 3 part per million (3 ppm). Any reading more than 3 ppm is too much chlorine.

For bromine, the ideal level is between 3 parts per million (3 ppm) and 5 parts per million (5 ppm). Any reading more than that is too much bromine in the water.

Other indicators of too much chlorine or bromine in the hot tub are corrosion of the shell and metallic parts of the hot tub, deterioration of the headrests, and worn out filters. If you notice any of these, then you might have too much chlorine in the water but the best way to be sure is to have the water tested.

Related Read: How To Raise Chlorine Levels?

2. Wait It Out

Vacate the hot tub for a while. If you leave the hot tub for a few days, the active chlorine or bromine inside the water will be used up over time and this will reduce the chlorine or bromine level.

If you have a chlorinator or any other device that automatically adds chlorine or bromine to the water at intervals, you should turn the device off or remove it from the water. The last thing you want is more sanitizer in the hot tub.

3. Remove The Hot Tub Cover

You can also remove the hot tub cover. You can also turn on the heater of the hot tub so the water is being heated while the cover has been removed.

The heater will heat the water and as the water evaporates into the air, the excess chlorine and bromine in the water are evaporated alongside.

You can leave the heater on for a few minutes and then turn it off. You can repeat this cycle for a few hours and then have the water retested again to check the chlorine or bromine level.

If you have your hot tub installed indoors, ensure to provide enough ventilation before doing this. After a few days (2-3 days), have the water retested. Chances are the chlorine or bromine level would have been reduced. If it hasn’t, don’t panic. There are still a few steps to carry out.

4. Add Freshwater

The step above where you heat the water and leave the cover open will get rid of excess sanitizer (chlorine and bromine) through evaporation but it will also reduce the water level in the hot tub since the water is evaporated with the chlorine and bromine. So you will need to add fresh water to the hot tub.

If the water level in the hot tub didn’t drop too much, you can remove some of the water in the hot tub and replace it with fresh water. Another alternative is to open the drain valve at the base of the hot tub and let some of the water escape. As the water escapes, so do the chlorine and bromine in the water.

After removing some of the water, you should add fresh water to the hot tub. This will dilute the remaining water in the hot tub and reduce the concentration of chlorine and bromine in the tub.

5. Turn on the Jets

After adding fresh water to the hot tub, turn on the jets for about 30 minutes so the water and sanitizers can be circulated (or mixed).

After this, take a sample of the water and have it retested. You should notice a considerable drop in the chlorine or bromine levels in the water at this point.

6. Last Resort

If you test the water and the water chemistry is still off or you are finding it difficult to balance the chlorine or bromine level, that usually means it’s time to drain and refill the hot tub. Chances are you haven’t drained the hot tub in a while. That’s why it is difficult to balance the water chemistry.

Related Read >>> Can You Use Chlorine Shock in a Bromine Hot Tub?

[su_youtube url=”https://www.youtube.com/watch?v=-YvGIanu3Ts”]

Can Too Much Chlorine or Bromine Hurt Your Hot Tub?

It hurts the hot tub when there is too much chlorine or bromine in it because the high sanitizer level will cause acidic water that can corrode and damage the working parts of the hot tub.

Too much chlorine or bromine in the hot tub isn’t only bad for you. It’s also bad for the performance of the hot tub. When there is too much chlorine or bromine in the water, the water pH will be very low.

The right pH level for hot tubs is between 7.2 and 7.8 on the pH scale. Most chlorine sanitizers have a pH level of 3 on the pH scale while most bromine sanitizers have a pH level around 4 on the pH scale.

This shows that the chlorine and bromine you add to the hot tub are already strong enough. So if you add too much chlorine or bromine to the water, it will produce acidic water in the hot tub and nothing degrades a hot tub faster than acidic water.

The acidic water can cause corrosion or etching. This means the water will start to eat away at the metal parts of your hot tub like the heater and circulation pump.

Hot tub water with high chlorine or bromine level can also damage the vinyl or acrylic walls of your hot tub by causing discoloration and staining. The hot tub pillows and filters will also get damaged when exposed to high chlorine or bromine levels in the water.

How to Prevent Having Too Much Chlorine or Bromine in the Hot Tub?

Follow the Instructions

The best way to prevent having too much sanitizer in your hot tub is to follow the instructions regarding the addition of the sanitizers.

Either you are using bromine, chlorine, or any other sanitizer to purify the water in your hot tub, your best bet to maintaining the perfect water chemistry is to follow the instructions regarding the application of the sanitizers.

Test the Water Chemistry and pH Levels

Another good measure is to regularly test the water chemistry and pH levels before adding chemicals. Don’t just add sanitizers based on intuition. Test the water first with your hot tub water testing kit. If you are sure the chlorine or bromine level is low, then you can add more.

If you add sanitizers based on intuition or because you can notice dryness of skin or any other symptoms, you may be adding too much chlorine or bromine. While some symptoms and indicators can tell if you have too much chlorine or less chlorine, these indicators are not usually accurate.

Most times, the problem might not be low levels of chlorine or too much chlorine. The symptoms might be caused by other issues concerning water chemistry. So the best way to be sure is to test the water regularly.

Drain the Hot Tub When Due

Look, we get it. Draining, cleaning, and refilling the hot tub is much work but it’s the best way to keep the hot tub safe and clean. Adding sanitizers to the water or shocking the hot tub is never a good substitute for draining, cleaning, and refilling the hot tub as when due.

Don’t just add a new dose of sanitizers hoping it will clean the water. While this might work, it is only a temporary solution, and it would even guarantee a high level of chlorine or bromine in the long run.

So when it’s time to drain the tub, just do so. You will be saving yourself a whole lot of trouble and unnecessary spending later on.

Recent Posts