Bromine levels too high after Non Chlorine shock

[999]

I use slow dissolving bromine in a floating dispenser and shock with non Chlorine shock.

I am finding that when i shock it the bromine levels go up to 10-20 ppm . It takes three days to come down to a level that i can use it. I am not keen on the smell either.

Thinking of changing to dichlor at my next water change. I presume i won't have the same problem after shocking

[chem geek]

If the bromine level is staying high, then you may not need to shock since apparently there isn't anything substantial for the bromine to react with.  Are you shocking because you believe you are supposed to on a regular basis or are you shocking because the water is turning dull/cloudy or you have some other reason you feel you need to shock?

With chlorine, you add enough after your soak to handle your bather waste and end up with a small amount of chlorine for the start of your next soak.  You normally do not need to shock if you consistently maintain a chlorine level (i.e. don't let it get to zero).

[999]

I was told that the bromine kills any bacteria and shocking oxidises organic waste, and should be done weekly or after a high bather load. I shock it every 7-10 days regardless. The water is always crystal clear and  have never had dull or cloudy water. I know that shocking reactivates spent bromine, but this reactivation gets the levels so high that I can't use it for up to 3 days.

If I use chlorine and dose it after use, how long will that chlorine last until it goes to 0 ppm. You say don't let it get to zero, but doesn't it disappear quite quickly. Presumably, I won't need to add chlorine every day? (I do have an ozonator as well if that makes a difference)

[chem geek]

If you aren't using the spa every day or two, then I would stick with your bromine tabs since that is an easier approach, especially having an ozonator.  If you use the spa infrequently, then using chlorine is more trouble because you need to add it every day or two or perhaps twice a week if you didn't have an ozonator, but with an ozonator the chlorine usage goes up if you aren't using the spa because ozone reacts with chlorine.  If you use the spa every day or two, then ozone oxidizes your bather waste so you end up using less chlorine, but if the spa is infrequently used then you end up using more chlorine.

For a bromine spa, your ozonator will also be generating additional bromine by oxidizing bromide to bromine.  Did you initially add sodium bromide after your fresh fill?  That would be the proper thing to do with the 3-step bromine system where you start off with a bromide bank and then use bromine tabs to provide a background level of bromine.  Even if you didn't, by now you've build up some bromide from all the bromine you've added over time (assuming you didn't just recently do a fresh fill).

With your ozonator, assuming it is working properly, I don't think you would need to shock to get rid of bather waste.  Most likely, the ozonator is oxidizing much of the bather waste and the bromine level you have is taking care of the rest as well as disinfecting the spa.  I suggest you just back off on the shocking and see how things go.  So long as you are measuring a background bromine level at all times (usually 4 ppm or so), your spa is being properly disinfected.

[999]

I started off using Jacuzzi products with my new Jacuzzi hot tub. I did enquire about using granular bromine to create a bromide bank but was told that it was not necessary and Jacuzzi did not do any such product forth use.

My water is now 3 months old so have no doubt built up a good reserve. Having shocked it 4 days ago it was still reading 10 ppm today, so have run it for half an hour to try and reduce it.

I use the hot tub about three times per week but because i work shifts it is used for three days in a row and then not used for the next three. However i do test dip it daily.

I think that i will change over to Chlorine in the next couple of weeks when i change the water, as i can always change back if it doesn't suit me.

[999]

Chem geek... thanks for the advice. Could you answer this question please.

I have read that when free chlorine reacts with bacteria it turns into a chloromine and this is what the chlorine smell comes from. Shocking the gets rid of these and the smell.

With regard to bromine. When this deals with bacteria it too turns into something else (not sure of what it is called) Is there an increased smell as these build up?

If i was to reduce the amount of shocking with my bromine would i notice an increase in the smell of it when it needs shocking or is that just when using chlorine.

[clover]

What you "smell" is a gas off the surface of the water.  This is usually caused by alkalinity or pH out of balance.  Bromine is typically on the lower end of the pH scale around 6.2 on the pH scale and you are trying to keep 7.2 to 7.6 pH. 

Check your alkalinity and pH.

[999]

I test dip my hot tub daily and always keep my alkalinity and PH correct. I have to increase the alkalinity around every 10 days, but that was what i expected.

Even with the alkainity and PH correct my bromine has a smell.... but does it smell more when it needs shocking.

[chem geek]

There shouldn't be enough bacteria to have any noticeable effect from the disinfectant since the whole idea is to kill bacteria faster then they can reproduce.  Yes, you shed bacteria, but you introduce a LOT more urea, ammonia, creatinine and other chemicals into the water and those are the ones that react with chlorine or bromine.  With chlorine, they produce various combined chlorine including chloramines while with bromine they produce the analogous bromamines.  The difference is that monobromamine is still a disinfectant while chloramine is not (or at least not very fast).  Both can smell at higher levels.

And yes, it is possible to build up bromamines if your bather load is higher and your bromine level lower.  Normally, they are broken down continuously, but if one gets behind then shocking will accelerate their breakdown.  Because chlorine tends to do a better job with oxidizing a variety of chemicals, you might try shocking with chlorine rather than with MPS to see if that makes any difference, though the end result of having too high a bromine level will be the same (unfortunately).  Also, with your ozonator, it is a bit surprising that you would need to shock at all since a functioning ozonator should be oxidizing bromamines.

As for what you smell when shocking, I'll bet that's bromine itself (bromine gas or gaseous hypobromous acid) since it's level remained high.  If you really had bromamines, then shocking with bromine would have the bromine level drop faster as the bromamine got oxidized.

So while it is possible that you might notice more smell if you shock less, I would guess that with your ozonator and the fact that shocking doesn't seem to use up bromine very fast that you won't notice any difference or any smell by not shocking, assuming you are always maintaining an appropriate bromine level.  If you have a heavier bather load, then you may need to add an oxidizer after your soak if the bromine tabs and ozonator are not able to keep up with that bather load.