I have read you can’t combine chlorine and bromine in a spa , yet when reading directions for shocking a bromine spa, many say you can use either non chlorine shock ( MPS) or chlorine shock ( Dichlor). Can someone please explain?
Combining chlorine and bromine/ shocking a spa
- Thread starter Sjde
- Start date
Oly
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Check this out......https://www.troublefreepool.com/threads/how-do-i-use-bromine-in-my-spa-or-pool.84/
Yes, I have read that and when it says-
“There is no advantage to using dichlor (stabilized chlorine) for shocking a bromine system but it probably wouldn't hurt.”
that’s when I wonder why, because isnt that mixing bromine and chlorine , which in other places I have read you should never do.
“There is no advantage to using dichlor (stabilized chlorine) for shocking a bromine system but it probably wouldn't hurt.”
that’s when I wonder why, because isnt that mixing bromine and chlorine , which in other places I have read you should never do.
Wherever you read that you should probably reconsider taking advice from that source. When you add chlorine to a body of water with sodium bromide in it the chlorine just activates the bromide in to bromine. In fact many bromine tablets have dichlor in them.
It was our hot tub manufacturer who said that.
And Swimuniversity-Whether you choose chlorine or bromine, DO NOT: mix them together in the water.
- This can cause a dangerous chemical reaction. If you’re going to switch from one to the other, you’ll need to drain and clean your hot tub, and do a line flush.
Oh no, not a DANGEROUS CHEMICAL REACTION!!!! Why, if you do that you might get... more bromine! 
Like I said, reconsider your sources. Those comments are demonstrably false. Chlorine and bromine regularly co-exist in a spa or pool because people don't have a large enough bromide bank. People regularly add sodium bromide to their chlorine pools to fight algae (something we DO NOT recommend) and that creates a bromine/chlorine situation. This is nothing unusual or new.
I do believe this isn't the first time we have had to correct some awful information from Swim Uni.
Like I said, reconsider your sources. Those comments are demonstrably false. Chlorine and bromine regularly co-exist in a spa or pool because people don't have a large enough bromide bank. People regularly add sodium bromide to their chlorine pools to fight algae (something we DO NOT recommend) and that creates a bromine/chlorine situation. This is nothing unusual or new.
I do believe this isn't the first time we have had to correct some awful information from Swim Uni.
And here's another example of conflicting information. As far as what the calcium hardness reading should be: SwimUniversity 175 to 275, poolcareguy-80 to 200, one CS person at our spa mfr-75 to 150 (for our acrylic spa), and another one there- 175 to 225. A test strip container--250 to 450. Frustrating!
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