bromine questions

hmls

Member
Dec 11, 2021
9
San Diego, CA
Hello everyone! I've finally got my spa up and running again and I have a couple of questions. Right now I'm following the 2-step bromine method and using Ahh-some's Aqua Clarity. Purged with the Aqua Clarity (surprisingly no gunk came out), refilled, balanced the water, established a bromine bank, and shocked with MPS. The tub has an ozonator that in theory is working. So, my questions...

1) I was using MPS because I had some, but I now have some liquid pool chlorine. Is it OK to just switch to using that?
2) I'm a little unclear on what to do before getting in the spa and after getting out. Do I test before getting in and add chlorine/MPS to raise the bromine if it's not 4-6? Same after we get out?

Thanks in advance for any help! I am sure I will have more questions.
 

YippeeSkippy

Mod Squad
Gold Supporter
LifeTime Supporter
Jan 17, 2012
19,316
Evans, Georgia
I'm sorry but once you've added enough Bromide to establish a bank of it any chlorine added just "revitalizes" the Bromine. You have a Bromine spa.... not something many here are familiar with since this is a chlorine based forum.
When people have accidentally used a lot of bromine in their pools we generally advise them to drain heavily and start again with chlorine.

For a spa we recommend this-

Maddie 🇺🇦
 
Last edited:

hmls

Member
Dec 11, 2021
9
San Diego, CA
Yes, I understand that, I am simply trying to figure out how to keep my hot tub safe and I'm a little unclear on the details for that which was the purpose of my second question. None of the links you provided answered that question. Also, if this is a chlorine based forum, why is there a bromine sticky at the top of it? If I thought chlorine would work for us, I would use it, but we travel so I can't rely on something that requires maintenance every single day.
 

hmls

Member
Dec 11, 2021
9
San Diego, CA
I'm going to ask my quesitons in a different way, this time with numbers!

Here is what I got when I tested this morning (again, this is the 2-step bromine system, I have not yet added a floater):
Br - 2.5
pH - 7.8
TA - 70
CH - 140

Since the sticky says to maintain 4-8 ppm of bromine, does this mean I should and MPS or chlorine to get it up to 4 before I get in the tub? I do have an ozonator which I believe lowers the recommendation to 2 ppm.

What about after I get out? Is ok if the bromine drops below what is recommended while I'm in the tub as long as it's not 0 when I get out? What if it is 0, what do I do then?

And then there is the party question... most of the time it is just going to me me and my husband in the tub, but I am sure we'll have friends over at some point who are gonna want to enjoy the hot tub too. What do I do then? Start with a higher level of bromine?

Thanks again for any help!

(Apologies if these are stupid questions. I've never owned a pool or a spa before and there is a lot of confusing information out there.)
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
36,551
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
I think you should add your chlorine or MPS after you get out of the tub. That then raises the bromine level and sanitizes the water. Your spa cover and residual bromine then keep the water sanitary waiting for the next use.

If you are going to party or spend a lot of time int he tub then you might add chorline before use to raise your bromine level.

Let's see what @RDspaguy says.
 

RDspaguy

In The Industry
Mar 21, 2020
1,569
Cabool, Mo
Let's see what @RDspaguy says.
He says "use chlorine". Dichlor/bleach is a good system. 😁

if this is a chlorine based forum, why is there a bromine sticky at the top of it?
This is predominantly a pool forum, and bromine is not recommended for pools. So there's not alot of bromine experience here. Someone who knows bromine wrote those stickys, but most of the folks on here regularly know nothing about it. There is a plethora of information on it available online. Bromine has been used in spas for a LONG time.

If I thought chlorine would work for us, I would use it, but we travel so I can't rely on something that requires maintenance every single day.
Chlorine will work for you, and does not require daily maintenance unless the spa is used daily. There are ways even if you will be gone months at a time. Perhaps you are asking the wrong questions?

do have an ozonator which I believe lowers the recommendation to 2 ppm.
Bottom line, sanitizer (chlorine or bromine) reacts with organic contaminants and is depleted. The more contaminants, the more sanitizer is lost. 2ppm bromine is not enough to destroy what you bring in to the spa, so is not sufficient to keep it sanitized during use. Ozone does not help with this at all. However, if you shock after use (destroying contaminants) and close your cover, 2ppm is more than sufficient to maintain sanitized water with no (or nearly so) new contaminants entering the water due to the closed cover.


What about after I get out?
Shock after use. "Shock" means "oxidize", and both chlorine and mps are oxidizers. Oxidation also converts bromide into bromine, so you destroy contaminants and create sanitizer.

And then there is the party question... most of the time it is just going to me me and my husband in the tub, but I am sure we'll have friends over at some point who are gonna want to enjoy the hot tub too. What do I do then? Start with a higher level of bromine?
This is where a spa get tricky. You cannot safely raise your bromine high enough to not be totally depleted by multiple bathers. Ozone, being an oxidizer, may help with this, but it may not depending on the system. 24/7 ozone injection would be the only one that would, but some control systems turn off the ozone when the jets, or anything else, is on. Under these circumstances a feeder of some sort would be needed, but these have their own drawbacks and should not be used continually under normal circumstances unless sensor controlled.
For example, you could drop a bromine tab in your filter well. This will help maintain the bromine levels during use, but will draw high concentrations through the equipment which will cause damage over time. Floaters tend to end up in the skimmer anyway, with similar effect, and create pockets of high concentration in the spa that can bleach/stain the tub.

Apologies if these are stupid questions.
The only stupid questions are the ones you don't ask. Everyone tends to think water chemistry is simple, a+b=x, when in reality it's more like [(a+b)/(c(d^3))× cos(b+d)]/ 4.7=x.😉
 

Jonsstihl

Well-known member
Sep 2, 2021
50
Quebec, canada
I sort of have the same questions, I have had my spa 1 week and I figured out for us that after use 2 adults 2 kids 1hr, I add 120 ml (1/2 cup) of liquid chlorine 10.5% and my CL is good the next morning. I'm down to testing daily instead of every 12 hours.

I think the solution is to test often until you get used to it. I was going to try and run it on Bromine but the spa store screwed up and gave me chlorine pucks so I am planning on switching to bromine after the next fill.

how long do you wait after adding chlorine to test the bromine level in a bromine spa. Is the reaction fairly instant to convert CL to bromine. and how long on average does it take for the Bromine to be "consumed" after a soak.
 

RDspaguy

In The Industry
Mar 21, 2020
1,569
Cabool, Mo
gave me chlorine pucks
Most acidic form of chlorine. Not, and I mean NOT, recommended for regular use. Quickest way to pay a guy like me a bunch of money on a regular basis is to use trichlor in your spa.

I am planning on switching to bromine
Why? Do you think it offers some advantage? In my experience the only 2 advantages it gives you are completely overshadowed by its drawbacks.
 

Jonsstihl

Well-known member
Sep 2, 2021
50
Quebec, canada
I figured out about the Trichlor by reading here, only put two pucks in before figuring it out. It has already discolored the end cap on my filter. I was thinking of using bromine because so far we don't like the feeling of chlorine on our skin and the way the water feels in the spa but to be honest it is not as bad as the begining, and I am getting the hang of it so we may not end up switching after all but I still would like to try it so that I can see what all the hype is about. I didn't get an impression there were many drawbacks to bromine can you elaborate? my spa is a basic spa no ozone or anything funky, just a pump to stir things around and a filter to remove contaminants.
 

Enjoying this content?

Support TFP with a donation.

Give Support

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
20,618
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Just a side note on some chemistry. MPS does a lousy job of activating the bromide bank into bromine. It's a very slow sanitizer system.

If your tub has a functioning ozone generator (they die pretty easily), then you can use bromine effectively because the ozone will create sanitizing bromine very quickly. The problem is, the rate at which it does that is only really suited for when no one is in the tub and it's cover is closed (basically standby mode). Once people start using the tub, then you need a fast method for creating the sanitizing bromine and the best way to do that is to use chlorine. You can certainly get into a tub with the bromine on the low side (no less than 2ppm) and then "shock" it after everyone gets out (add enough chlorine to raise the Br reading up to 10-12ppm). Then just test it occasionally until you plan to use it again. If the plumbing is clean and the ozone generator is functioning ('why does he keep emphasizing that' you might be asking ...), then a post soak shock should be able to handle much of the bather waste before the next soak.

No matter what method you use, there is no "set and forget it" hot tubs ... you have to test them a lot and keep an eye on their operation and water chemistry. Everyone loves the idea of having a hot tub but few love the idea of actually taking care of one.
 
  • Like
Reactions: RDspaguy

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
20,618
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
One other method for running a bromine tub in more of a set it & forget it mode is to use a drape over the side SWG. You can add enough salt to the water to get the SWG to run and then you can run the chlorinator. It will create sanitizing bromine right away and can act as your residual method for keeping the tub sanitary while it is in Standby mode or if you happen to be away on vacation for a while. You really only need to set it so that your Br levels stabilize around 2-4ppm (more than enough for standby sanitation) and then just keep enough dichlor or liquid chlorine on hand to bump up the bromine levels after a "human soup" party.

The only hitch is that you need to ensure that your hot tub equipment is compatible with saline water (I hate the term "salt" water ... it's not very salty). That mostly means you should have the heater replaced with a high quality titanium heater element. If not, the higher chloride ion concentration will cause premature failure in steel or Incoloy heating elements.
 
Thread Status
Hello , This is an inactive thread. Any new postings here are unlikely to be seen or responded to by other members. You will get much more visibility by Starting A New Thread