Just as a suggestion you might want to visit www.poolspaforum.com. They have a LOT of info devoted to spas including how to do the bleach/dichlor method (BBB for spas) and the proper way to do 3 step bromine. There is really not a lot of spa info on this forum, it's devoted more to pools while poolspafourm is much more active in the spa sections of the forum.

(Mods or Ben, if you have any problems with this post directing someone to a different forum feel free to delete it. I'm just trying to be helpful.)