Bromine is best for spas and hot tubs, for many reasons. it’s more stable in hot water and is affected less by wide swings in pH.
There is one trick you should know about using spa bromine. I’m speaking of Building a Bromine Bank.
The ‘bank’, is actually a reserve of sodium bromide ions in the water. For bromine to be effective, enough bromides need to be available.
Each time you drain your spa or hot tub, your bromide bank goes to zero. To build the level back up again you simply add granular sodium bromide. Brom Booster, as it is known, is 100% granular sodium bromide. Use 2 oz. per 500 gallons to build up the bromide bank in your spa.
You could allow the bromine to come up slowly on it’s own, from the dissolving bromine tablets, but it can take days or weeks before you begin to see a bromine reading in a spa or hot tub.
You could also crush up 5 or 6 bromine tablets, in a heavy plastic bag, and pour that in the hot tub to raise bromide levels – but, it’s easier and safer to shake in a capful or two of our Bromine Booster.
The other side of the bromine equation involves activating the bromide ions with spa shock, which converts them to hypobromous acid, the killing form of bromine.
In the normal 3-part bromine system, a spa owner starts with a residual of bromide ions in the water, and then add the bromine tablets to a feeder or floater. There is no home test for measuring bromide ions in your spa, just add the recommended dosage for your spa size.
Shocking weekly with spa shock activates the bromide, or converts it into hypobromous acid, or HObr. Once HObr has attacked a contaminant in the water, most are reduced back to a bromide ion again, where the cycle begins anew.
The beauty of InTheSwim bromine tablets, as detailed in my previous post, is that they contain 27% chlorine! This acts as a built in oxidizer to keep the bromide ions constantly converting a continuous supply of HObr.
So, you don’t really need to shock a spa or hot tub to “activate” our bromine tablets. However, I do recommend that all spas be shocked weekly, more for sanitation purposes, but also to ensure adequate conversion of bromide ions.
You will find that after oxidation of your bromides, using a non-chlorine spa shock, that your bromine level will spike, and that’s because you are really shocking with bromine! The non-chlorine shock is oxidizing contaminants when added, but quickly mates up with free floating sodium bromide ions, to create HObr, which is when the real fun begins!
I’ll leave you with some chemist humor, and the hope that you now know at least something about sodium bromide, or NaBrO.
If you have other questions about spa shock, spa tablets or sodium bromide, give our spa techs a call, or send me an email.