How do I use Bromine in my spa (or pool)?

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You can use The Pool Calculator to calculate dosages of Dichlor or bleach to get to a certain Free Chlorine (FC) level. The bromine level that results when you have a bromide bank is simply 2.25 times the FC level. So if you shock to 10 ppm FC, you end up with 22.5 ppm bromine. Note that simpler test kits have a dual bromine/chlorine scale which they simply to use a factor of 2 though it is really 2.25.

So to go backwards, if you want to get to 15 ppm bromine, then you need to add 15/2.25 = 6.7 ppm chlorine.
 
If the bromine level holds right away after a fresh refill, then there isn't any need to shock at all. Same is true with weekly shocking -- no need normally. Shocking is something that is done when there is a problem -- some unusually higher disinfectant/oxidizer demand. If you are able to start out maintaining 5-10 ppm bromine right away, then you're good to go. If you find that the water is getting a little dull or cloudy, then you can shock with chlorine -- probably around 10 ppm chlorine which would be 22.5 ppm bromine -- and if necessary that would be the shock level after a fresh fill if you find that your bromine level isn't holding. Chlorine can oxidize some chemicals better than bromine so if you aren't really clean getting into the spa then you may need to shock more frequently, but if you are relatively clean, then the chemicals in your sweat and urine are usually handled reasonably well by bromine.
 
Ok i get all of this but what i am referring to is part 2 of the How do use bromine in my spa thread where is says to shock the spa (maybe this is worded wrong and just means oxidise the bromide with chlorine to get the bromine level up straight away rather than waiting for the tablets to start dissolving) this is the first initial bromine level that im referring to. Do i just add enough chlorine to get the bromine level to 5-10ppm
 
Just add enough chlorine to get the bromine level to 5-10 ppm. If it seems to hold, then you're set and the tabs should take over from their in maintaining it. If it gets used up within a day or 24 hours, then you need to shock higher, say 10 ppm FC for 22.5 ppm bromine. Most likely, though, you'll not drop much and the bromine tabs will be able to maintain the level for you if you set the dial of the floater appropriately. If you have an ozonator, you may not need the tab feeder turned up as much or perhaps not even need it at all.
 
I am getting a new Hot Tub in Beijing China next month. It should hold about 500 gallons of water.

Getting pool chemicals is a chore in beijing especially when you don't speak mandarin. Locals don't know much about pools here as they are very rare luxury items in a society of high rises. Pools tend to be large public pools with industrial sanitation systems.

The hot tub I'm buying from a south China manufacturer includes an Ozonator and a USA Built Spa pack. I was thinking of adding a Copper/Silver Ion system to it but figured I still needed to use some other sanitizer and certainly still need to shock on a bi-weekly or so basis. Back home I had a Bromine Hot Tub (3 part) system and it was fine. As long as I changed the water every three months I never had any issues with it, even during harsh canadian winters.

I think I can get Chlorine in Calcium Hypochlorite form, I doubt I'd find CYA locally, (I'll be getting a list of available chemicals Monday from an agents for an Australian Firm called Waterco that i was able to find) getting a good test kit and reagents may also be a challenge.

with all the heavy metals in the air in China I can imagine there will be some high metal content in the water. I expect the water will be quite soft as Beijing is over a geo thermal area so I,d expect the water to have a certain lime distillate in it. These are assumptions at this point.

My question is, after reading certain posts, that perhaps the Copper/ion system is a waste of time. BBB is doable except for the stabilizer which may be a problem. If I did use the Ozonator and the Coper ion system I was hoping a quick shock of straight liquid chlorine every now and then would do provided I keep the TA and Ph in balance.

I had read about the Nexa SWG system, but adding electrical items from the outside without a proper GFI in the electrical panel gives me the willies. Getting one for the Hot tub is enough a chore, especially since the house is a rental.

I also read about some other sanitzing systems, Chemical sanitizers that are "natural" not sure I can find the here but I have't seen a lot written up on these.

Feed back is welcome,
Thanks
Shatsmtl
 
Much of the Trichlor and Dichlor is made in China and imported here so I'm sure you'd be able to get "chlorinating granules" or whatever they call Dichlor there. Are you able to find bleach? If so, and if it's not horribly dilute and high in pH, then you could use Dichlor-then-bleach as described in Using Chlorine in a Spa. Note that your ozonator will only be helpful if you use the spa every day or two. If you don't use your spa that often, then the ozonator will end up increasing chlorine demand since ozone reacts with chlorine.
 

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I'm confused...

I refilled my hot tub about 2 months ago at the beginning of August. I was using chlorine to sanitize, adding bleach daily....and I added dichlor to bring CYA up to around 30.

At the beginning of September, I went away for 8 days, and didn't have anyone to hot tub sit. Per chem geek's recommendation, I raised FC to 10 and added 1 bromo/chloro tablet to a bromine feeder (set to about 4, basically making the tablet completely open to passing water)....all that info is detailed in the "hot to use chlorine in your spa" thread. I'm posting in this thread now because I'm trying to use bromine now, as I don't use the hot tub daily and don't want to have to add chlorine daily.

So, since the beginning of September, I've been using a bromine tab in a floater. I've been keeping an eye on the amount the tablet is dissolving, and basically have been adding 1 tablet a week to the floater as the tablet dissolves to about half or less of what it was.

I haven't been monitoring levels of bromine, and I don't really understand what I'm supposed to be doing.

I just did the OTO test, and bromine level appears light, like 1ppm.

I just added 6 oz of 12.5% bleach....


What am I doing right and/or wrong here? What do I need to be testing, and how often?

Thanks for all the help, and your patience with this hot tub newb.
 
The bromine tab will only give you a low background level of bromine. If you have the feeder open all the way, then you might need to use two tablets instead of one if it isn't dissolving fast enough to have 2 ppm FC or 4-5 ppm total bromine (they are the same thing, but in different units of measurement so depends which scale you are using -- I presume you have a chlorine test kit so multiply the FC by 2.25 to get the Total Bromine level). You should test with your more accurate FAS-DPD test kit and just multiply the FC result by 2.25; it's more accurate than the OTO test.

The tablet will not be enough to oxidize bather waste from your soak so you will still need to add an oxidizer (bleach, dichlor or MPS) after your soak just as you did when using chlorine. The difference is that in between soaks, the bromine tab should maintain a sanitizer level in the spa.
 
I just did the FAS DPD test and FC measured at about 1....so bromine level would be 2.25?

I added another tab to the floater, so now there's 2 whole tabs and a few little chunks from previous tabs.


To confirm: I should keep bromine level around 5?

Should I be running a full test on the water for CC, TA, and CH? If so, how often?
 
Yes, with an FC of 1.0 your bromine level is 2.25 ppm.
You can shoot for an FC of around 2 ppm which is a bromine level of 4.5 ppm.
With bromine, you don't test CC since combined bromine shows up as FC so you are really measuring Total Bromine.
TA and CH are still relevant for the saturation index to prevent scaling and pH and TA are relevant for how fast your pH may rise (i.e. you adjust TA to find the sweet spot for pH stability, but note that bromine tabs are net acidic).
 
I just added 3 oz of 12.5% bleach to bring FC up to 6.

Since I'm using a bromine floater, that bleach I just added will basically convert bromide to bromine over the course of an hour or so?


I just tested the hot tub water:

pH 7.8

TA 70

CH 210


looking good?
 
Yes, the chlorine (or any strong oxidizer such as non-chlorine shock MPS) you add will convert the bromide to bromine, probably sooner than an hour. Your numbers are OK but your CH is higher than it needs to be to prevent foaming. Usually 120-150 ppm is sufficient for that. If the CH gets too high, you can get scaling, though your OK right now.
 
just tested the water while my wife is in the tub for about 15 minutes.....

FC is showing up as 1.5, so bromine would be 3.375...


Should I add some bleach while we're still in the tub, or wait until after? What FC level should I be shooting for when I add bleach?
 
Unless you are swimming with strangers with whom you are concerned to get disease from person-to-person transmission, I'd just add an oxidizer (such as bleach) after the soak to handle the bather waste. You add enough so that you start your next soak with around 2 ppm FC. If you were to add a disinfectant or oxidizer during your soak or before your soak, then you'd likely smell it and not be as pleasant for you.

Even with a sanitizer getting very low to zero during your soak isn't bad since you don't soak for more than one hour and you will blast anything in the spa by adding something right after your soak (and technically some of the sanitizer will become monobromamine in a bromine spa which is still a disinfectant or monochloramine in a chlorine spa which still kills, but more slowly). So having a small starting sanitizer level before your soak is reasonable unless you are treating your spa more like a commercial/public spa where anyone with a disease can be soaking with you.
 
chem geek said:
Yes, with an FC of 1.0 your bromine level is 2.25 ppm.
You can shoot for an FC of around 2 ppm which is a bromine level of 4.5 ppm.
With bromine, you don't test CC since combined bromine shows up as FC so you are really measuring Total Bromine.
TA and CH are still relevant for the saturation index to prevent scaling and pH and TA are relevant for how fast your pH may rise (i.e. you adjust TA to find the sweet spot for pH stability, but note that bromine tabs are net acidic).
Click to expand...



So, using bromine tabs will lower pH?

If pH is just below 7.2, what should I do to get pH higher?
 

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