If you want to change your spa or hot tub from Chlorine to Bromine, you can do it at any time.  Simply begin adding bromine.  There is no need to empty the spa and start again.  The bromide salts that are an integral part of any bromine product stay in the water.  The bromide salts will be activated by the chlorine. They don’t dissipate; they don’t gas off into the air. The only way to get bromine out of the water is to get rid of the water! If anything, bromine reverts back to sodium bromide until it is “recharged” back into active hypo-bromous acid or as we refer to it, bromine.  You could also dilute it way down, however, you will have a bromine spa until it is drained.

Converting your Spa or Hot tub from Bromine to Chlorine

In converting your spa or hot tub from Bromine to Chlorine, there’s only one thing to do:  drain the spa and change the water.  To be sure that ALL of the bromine is out of the spa, you may have to drain and refill the tub a couple of times.  Remember that you’ve got to get the brominated water that is in the lines diluted and out.