This is the question I am asked the most – Is bromine better than chlorine to sanitise my hot tub and keep the water crystal clear and safe? The majority of hot tub/spa dealerships will say bromine is the best chemical to sanitise your hot tub or spa and list at least four good reasons. BUT, chlorine might be better for some people. In this article, I will detail the advantages of bromine, but will also explain why Chlorine might work better for some of you.
The Cost
Bromine will cost you more than Chlorine. About 30% extra depending on the system you use. As with chlorine, you can buy the sanitiser as tablets which dissolve over time slowly or as granules that you add daily.
So chlorine is the cheaper option for your hot tub, and if you have just bought an inflatable hot tub, like a lazy spa, Chlorine might be the easiest option to start using. You can also use the chlorine granules to ‘shock your hot tub weekly another cost saving!
Hot tub smell
Bromide sanitised hot tubs give off less odour. This is because when chlorine kills bacteria, it creates chloramines. These chloramines smell (Think public swimming pool smell!). I do not find the smell offensive, but some people might. Generally, if your hot tub or spa smells and your sanitiser levels are sufficient, then it is because the ph level is incorrect. A perfect pH is between 7.4-7.6 range. Anything outside of that range will result in odour. I have written more about bad smelling water and solutions in another article.
Skin rash and sore eyes
The chloramines not only smell, but they can also irritate your eyes and skin. Chloramines are not produced when a bromide sanitizer is used in your hot tub or spa, which is another reason why some hot tub owners prefer bromine. Some people are more sensitive to chloramines than others, and even if you have a high concentration in your hot tub, you may not be affected. Generally, people do not submerge their head under the water and open their eyes!
I found my chlorine sanitised hot tub, on occasions, made my eyes a little bloodshot and sore when the jets were on full blast. This is because the bubbles would cause small particles of water containing the chloramine to get into my eyes. However, chloramines are not dangerous, and the irritation passes after an hour or so. I might have also been affected more because I would regularly spend over an hour in the hot tub!!
Saying that I used chlorine in the hot tub for over two years, so it couldn’t have been that much of an issue for me.
Bromine is more stable than chlorine at high temperatures
This is a fact. Chlorine at high hot tub temperatures breaks down much faster. But is this a problem? Not really. To maintain your hot tub or spa, you will need to be testing the water quality regularly and adding more sanitizer as required. It’s true that after you have owned the hot tub for a few months, you will begin to know the quantity of chemical needed. These will vary depending on the frequency of use, but also on other factors, like if you shower before entering the spa! That being said, testing the water quality is mandatory to ensure the water is safe to use.
Click here to read an article on hot tub infections caused by unclean hot tub water – it might give you the motivation to test the water regularly!!
Granules, dissolvable tablets or cartridges?
So have you made your decision yet? Yes… GREAT. Now you need to decide on the sanitizer delivery method. As with the famous chlorine v’s bromine debate, everyone has an opinion of what is best. I’ll try and be unbiased and give you the advantages and disadvantages of all three.
Dissolvable Tablets (Chlorine or Bromine)
These are generally placed in a plastic container that floats in your hot tub all of the time. The dispensers usually have adjustable holes in the bottom that you can use to try and regulate the amount of chemical dispensed into the water. I say “try”, because I found that in reality adjusting the size of these holes made little to no difference! The argument for the dissolvable tablet method is that it is easier. The suggestion is that you can neglect your hot tub and it will need less maintenance. Unfortunately, this is not the case. To keep the water safe, you will still need to check the water regularly, and if you find that the chemical level is below what is required, you will need to add more in the form of… yes, granules!
Granules (Chlorine or Bromine)
As established above, you will need to be topping up the chemical level regularly with granules, regardless of which delivery method you use, so why not just use granules in the first place. This was my thinking and the fact that granules are cheaper sealed the deal!
The argument for using dissolvable tablets in addition to the granules is that the chemical level does not fall too far below the safe level. I think this is probably true if you only use your hot tub or spa every couple of days. I generally tested the water quality every morning and needed to add about a teaspoon of chlorine granules. I would also add a teaspoon of chlorine granules after I had used the hot tub in the evening. (Using Bromine granules you would have a similar routine, but the amount of chemical needed would be less.)
I know by testing that topping up the chemical in the morning and evening after use was perfectly acceptable and the chlorine level would never drop to unsafe levels.
So, what do I use now in my hot tub?
I changed over to bromine about two years ago when I decided to upgrade from an inflatable hot tub to a larger solid tub. Chlorine was excellent for the inflatable hot tub, and from memory, the hot tub came with a large tub of chlorine that lasted over six months. The new hot tub had a bromine cartridge system built into the filtration system, so it seemed sensible to change at that point. I use Spa Frog and this link will show you to the latest price on Amazon. You can alter the amount of bromine levels released into the hot tub to suit your level of use very quickly. It is more expensive, but you can bulk buy on Amazon, which reduces the cost a little.
The Spa Frog system does not have to be built into the hot tub. You can buy a float, and attach the two cartridges to this.
What should you use in your hot tub or spa? Chlorine or Bromine?
In my opinion, chlorine wins if you are buying your first inflatable hot tub. It is easy to use and cheap. You can use the same chlorine to shock the hot tub, which again makes the whole experience simple. To learn more about maintaining the water quality in your hot tub click here! to find an article where I give some great top tips!
That’s the end of the story … Right? … No!!
There are other sanitisers that you can use in conjunction with either chlorine or bromine. They add an extra layer of safety and mean you can use the minimum amount of chemical, which has to be a good thing.
Mineral sanitisers
I have already spoken about the Spa Frog system, and this uses a mineral cartridge that lasts about four months. The cost is around £20 /$20, and the cartridge can be used with either chlorine or bromine.
Mineral sanitisers contain metal ions in activated charcoal. They are antibacterial and anti-algae and add an extra layer of protection to your hot tub. They are also odourless.
Many hard hot tubs have a cartridge holder built in, so it makes sense to use it if so. I would recommend them for your inflatable hot tub only if you are going to use bromine with the spa frog. Otherwise, I would probably give it a miss.
If you have an inflatable hot tub, you can ignore the next two as they only apply to hard hot tubs.
Ozone sanitation
Ozone is a very effective sanitiser and should be used with either chlorine or bromine solutions. As with mineral sanitation, ozone allows you to use fewer chemicals. To be clear, by less, I mean at the lower limit of the recommended level. Ozone devices are built into your hot tub and do require some maintenance that I will detail in another article.
UV sanitiser
These devices use ultra-violet light to kill micro-organisms. Those reading who keep Koi fish will probably already be using one! As the light is produced using a bulb, it will need replacing, over time, according to the manufactures instructions.
Lastly – How to go about changing from chlorine to bromine.
The two chemicals should not be mixed so if you are changing the sanitizer; you should do this when you change the water. As a rule, I generally change the water in my tub every four months. This may be a little too much, but my family and I use the hot tub every day, so I like to change the water and clean the pipes at the same time.
Thanks for reading!
Brendan :-)
