What is the best bromine chemistry for indoor pool

[tstephens3956]

I have and indoor lap pool, 18000 gallon, gunite, sand filter. The original installation used the combination of a Nature 2 purifier/filter plus low level chlorine sanitizer to keep down the chlorine smell in the walk out basement area. The Nature 2 filter housing failed twice and the last time I was convinced by a pool service to eliminate this element and switch to bromine since the bromine smell is lower. Since the pool stays filled and warm year round, there is a lot of evaporation and build up of solids/alkalinity. Last week the chemistry more or less crashed and I could not keep the pH down in the normal range and the water would not stay clear. I decided yesterday to drain and refill so I could start from scratch. I am using DCDMH pellets in a floating brominator to brominate. My question is what is the best way to get this 18000 gallons of fresh water built to a good total bromine level? Should I add sodium bromide? What is the best way to shock the pool? I prefer to use as limited chemicals as possible and chemicals that do not add significant alkalinity/solids because of the evaporation problem. I adjust pH down with muratic acid. What is your advice?

[chem geek]

Yes, you could add sodium bromide to create a bromide bank though eventually the use of bromine tabs will build that up over time as the bromine is used. By the way, the smell from chlorine may have been because you didn't have any Cyanuric Acid (CYA) in the water, unless you were using stabilized chlorine. As for shocking, chlorine bleach (unscented, plain) is the easiest to use for that purpose. It will convert the bromide to bromine and the chlorine will convert to chloride salt. So your pool remains a bromine pool.

[tstephens3956]

Thanks Chem Geek for your reply. I also asked this question in other forums and got different answers. Local pool supply shops suggested to not use a chlorine based shock because of the generation of unwanted chemistry in a bromine pool (don't remember now what that was supposed to be). In any case, I went with a non-chlorine shocker. I understand that with the DCDMH that shocking is not as necessary but I did use shocker with all the fresh water. In any case, the bromine testing seems to be good. The stabilizer, cyanuric acid, I understand to be required for chlorine in outside pools to protect from breakdown due to UV light. In any case, my understanding was that mono-chloroamine was the cause of chlorine smell. My pool is indoor and is directly attached to the basement floor in a walkout configuration. Still there was some cyanuric acid in the pool even though it should not be required. In any case, this configuration is very sensitive to the chemical smell. I have now moved on to a different issue, replacing the sand in my filter since the clarity is not very good right now. I am weighing the options of putting sand in the filter again versus zeolite or ground glass. I get really mixed messages on the zeolite and the locals recommend against it. There is less objective information on glass but it does appear to last longer while being more expensive. I have found one objective article on the topic published by the CWC claiming that water clarity is better with glass while requiring less material. I will start a new post on this to get some feedback but here is a link to that study: http://www.cwc.org/glass/gl981rpt.pdf