Bromine Reserve

[Zadd]

Question: how many lbs of Bromine tabs would it take to build an adequate sodium bromine reserve in a 177k pool?

We will be doing some renovation on one of the pools this August and I would like to only meet the min reserve requirements to make it a bromine pool. Assuming I can keep reserve down to a min. I think keeping a lower ppm as possible for the public would be best. Right now I have twelve years of Br tab use and the reserve must be extremely high because I can't hold 4.5 ppm without algae taking over. Advice?

 

[Madison Mike]

Assuming a rate of 1/2 ounce per 100 gallons of water, I come up with 55 lbs of sodium bromide. You wouldn't use tabs for this, as they have chlorine and bromine in them to mix with the sodium bromide to create hypobromous acid. I think I got that right!

 

[JasonLion]

Bromine tabs will eventually build up a bromide reserve, though I don't know how quickly. But "reserve must be extremely high because I can't hold 4.5 ppm without algae taking over." doesn't make sense to me. The size of the bromide reserve doesn't really have anything to do with getting algae or not, at least that I can think of related to high levels.

 

[Zadd]

Bromine tabs will eventually build up a bromide reserve, though I don't know how quickly. But "reserve must be extremely high because I can't hold 4.5 ppm without algae taking over." doesn't make sense to me. The size of the bromide reserve doesn't really have anything to do with getting algae or not, at least that I can think of related to high levels.

I thought I read on here that a high bromine reserve would act similar to high CYA like in outdoor pools? So the best way to do this is without tabs and just add sodium bromide?

 

[chem geek]

It's not the bromide reserve that acts like CYA, but rather the DMH leftover from use of bromine tabs (BCDMH or DBDMH) that could act like CYA at high levels. So you want to avoid use of the bromine tabs and just use sodium bromide at the dosage indicated. Then use any oxidizer to convert the bromide to bromine.

However, why do you want a bromine pool? It generally costs more and bromine is not as good an oxidizer as chlorine so if you don't use chlorine to produce more bromine your pool can end up getting cloudy. I did read in your signature that you have two indoor bromine pool facilities so I suppose you are just keeping things as they are. The other reason to avoid bromine is that it produces worse disinfection by-products (the brominated THMs are worse than the chlorinated THMs, for example).