Problems with Bromine Pool

Jump to latest Follow Reply
T

TreeFiter

0
LifeTime Supporter
In The Industry
Jul 2, 2012
449
Saugerties, NY
I have a customer with an indoor pool that has turned cloudy. The pool is about 20,000 gallons and uses Bromine. The pool turned because we were not able to service the pool for several weeks.

When I found the pool was cloudy, I added 4lbs MPS, and 2lb trichlor. I followed up several days later and added another 4lbs MPS and 6lb trichlor. The pool hadn't improved. One week later, I found that the pool was still cloudy with no noticeable improvement, but the FC/Br tested greater than 10 (FC) on a test strip (I know, test strips aren't very reliable, but for a ball park like greater than 10 it should be good enough). I also adjusted the pH accordingly each time.

I returned once again a week later (tonight) and found that it was still cloudy and the chemistry hadn't changed. This time I tested with FAS-DPD. I got FC=8.5 (if I'm not mistaken, this should be doubled for Bromine) and CC=2


Full Results:
FC=8.5
CC=2
pH=7.5
TA=100
CH=240


When I added the trichlor shock, the pool released an overwhelming amount of chlorine gas (I assume, but maybe it was chloramines) almost instantly. The water coming from the return jets turned yellow.

So if I'm understanding how this is supposed to work, CYA is not a factor because we are dealing with Bromine. So if I'm getting FC=8.5 (Should be 17 or more for Bromine), I'm well above Shock levels, and it seems to be holding. I would expect to see it drop if it was fighting biological growth or getting rid of Chloramines/Bromamines.

So why isn't this pool clearing up? Any suggestions?
 
If it's a bromine (Br) pool than I'd state what you have for bromine and not FC. IMHO That would make it a bit more clear that you understand it's bromine and so would someone reading it.
Is the pool plaster or fiberglass or vinyl or ... ??
What kind of filter does it have and how many hours per day is the pump running ??
Any chance you have a photo of the water ??
 
The pool is plaster with a sand filter. It has been running 24/7. I don't have a photo.

I posted numbers for FC because I wasn't completely sure how they translate to Br. I believe it should be FC x 2.25, but I figured if I provided the information as FC and explained that it was Br it would be better than providing incorrect numbers for Br.
 
The water turns yellow due to high levels of elemental bromine. I'm assuming that you're pouring the trichlor through the skimmer. If that's the case, the ph drops and the bromine level is high creating enough elemental bromine to color the water yellow.

Following the SLAM process might help. Trichlor is not the best choice for chlorine. Bleach would be a much better choice.

There is a lot of information that would help us help you. Such as:

Is the pressure going up?
When you backwash, what does the waste water look like?
Is this pool being used? (It should be closed).
What is the daily bather load?
When was the pool last filled?
How many total pounds of bromine tabs have been used since the last fill?

This is going to require at least daily visits to clear. Once a week won't work. You might want to set up a side system with a DE filter to speed up the process.

You might want to do a drain and refill if that could be done safely.
 
As far as following the SLAM process, the pool has maintained elevated Br levels for two weeks, but has not cleared up. I'm not really sure how this differs from the SLAM process. Correct me if I'm wrong, but SLAM requires the sanitizer be elevated to shock levels and maintained until it passes an overnight drop test. In this case it maintained significantly elevated levels for two weeks with no signs of improvement.

The pressure is not rising significantly, but the backwash is cloudy. The filter is only about a year old. The pool is not being used at this time. I don't know when the pool was last filled. The total amount of Bromine tabs added is over 50lb. Tablets were added weekly for a long time. It wasn't until recently that I stopped adding tablets and started using an oxidizer to re-activate the bromine.

Daily visits probably aren't an option, but a few times per week is likely a possibility. I don't think a drain/refill will be an option either. This particular customer is a pain in the butt, and wants only to place blame rather than do what will fix the problem.

I don't understand how the size of the Bromide Bank would be a problem. From what I understand, the bromide doesn't do much, but if there is excess, it would allow for higher Bromine levels when oxidized.

One of the problems I have encountered with this pool is the offgassing of chlorine. Because it is an indoor pool, this is a much bigger problem. When I added chlorine to the pool, the room was filled with chlorine gas to the point where I couldn't stay inside. I had to ventilate the room for about a half hour. Is this an expected reaction, or is this more likely chloramines forming?
 
The bromide probably isn't causing problems. I was thinking about the level of DMH, which can cause problems with bromine similar to cyanuric acid in a chlorine pool.

I suspect that the pH might be very low and reading a false high due to the high bromine.

A drain and refill would probably be the best option.

Note that drainning and refilling has risks and should only be done if it can be done safely.
 
This thread:
http://www.troublefreepool.com/threads/27824-Couple-questions-about-fecal-accident-response

has interesting discussion of the possible problems resulting from excessive levels of DMH, with links to references.

I remember reading another thread where a pool owner described intense chlorine odor caming off a bromine pool after using chlorine shock. There was a response suggesting that this was due to high levels of organics in the water; in other words, the bromine in the pool wasn't adequately sanitizing organic matter (perhaps because of excessive DMH). I guess that goes along with your suspicion that you were smelling CC compounds.

I don't pretend to understand the chemistry myself -- just passing on a thread that appears to contain relevant information from more knowledgeable posters (JamesW and chem geek both contributed to the linked thread).
 
In this case the poster says that more than 50 pounds of bromine tabs have been used. Without knowing exactly how many pounds of tabs have been added, it's probably best to be cautious and assume the worst especially since the water quality is very poor and not improving.

With a fresh fill, one can be more vigilant about maintaining good water quality through proper chemistry.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Somehow I managed to walk away from this post without seeing the last few comments. I was actually at this same pool today because it had the same problems again. Last time we ended up doing a phosphate treatment, which cleared up the pool, but here we are 2 months later doing it again. For the record, I was against the phosphate treatment. So this time, my boss went ahead and did another phosphate treatment.

The customer is not likely to go for water replacement. There has been a huge amount of Bromine added in the form of 1" tablets. The problem is going to keep coming back unless I can figure something out.

I read through the thread suggested above regarding DMH. A few questions come to mind. Does DMH interfere with sanitizing proportionally? In other words, at 10 ppm it interferes a little bit, but at 200 ppm it interferes a lot. Where I'm going with that question is, would a bromide bank established with tablets result in less potent sanitizing ability than in the case of a bromide bank established by sodium bromide?

What other options could keep this pool clear if the customer refuses to replace water? Would Polyquat be a viable option? Would it be worth it to regularly add a phosphate remover to prevent algae growth? (I'm thinking no, because we still have bacteria to worry about.) I'm thinking adding any more Bromine tablets is a bad idea.
 
The problem with dmh is that we don't know the equilibrium constants for it with bromine like we do with chlorine and cya. The reason that chlorine tabs are made with cya is because the chlorine forms stable compounds with it. Dmh is chosen for bromine for the same reason.

I think that the chemistry is similar in that the ratio of br to dmh determines the effectiveness of the bromine by controlling the amount of hypobromous acid in the water.

I think that unless the amount of dmh is substantially reduced, the pool is going to be very difficult to impossible to manage.
 
JamesW said:
The problem with dmh is that we don't know the equilibrium constants for it with bromine like we do with chlorine and cya. The reason that chlorine tabs are made with cya is because the chlorine forms stable compounds with it. Dmh is chosen for bromine for the same reason.

I think that the chemistry is similar in that the ratio of br to dmh determines the effectiveness of the bromine by controlling the amount of hypobromous acid in the water.

I think that unless the amount of dmh is substantially reduced, the pool is going to be very difficult to impossible to manage.
Click to expand...

I think you may be right. It really sounds like the only thing that will fix this pool is replacing some water.

In the current state of this pool, with a huge Bromide bank and who knows how much DMH, how might I attempt to keep it going with MPS? As I think about it, I don't see a way to make it work well, especially since the pool only gets maintained every other week.

If the Bromine bank were just right, I could dose heavily with MPS, and as long as there was excess MPS in the pool, the Bromine level would stay maxed out, right where it needs to be. Is there any reason high MPS would be a problem?
 
I think that the only solution is to replace most, to all, of the water.

Note that there is risk in doing a full drain. A full drain should only be done if it can be done safely.
 
In an outdoor pool you will lose both MPS and bromine to sunlight (MPS more slowly?) My understanding (not confirmed) is that DMH does not protect bromine from sunlight the way CYA protects chlorine. If that is true, you will need really really extreme levels to go a week between chemical additions.

Also, my assumption is that the bromide bank is very very high. If DMH is really high, bromide should be equally high. The MPS is likely to convert lots of bromide to bromine and get used up fairly quickly.

If they won't agree to replacing all of the water, what about replacing an inch of water each time you are there? That way there would at least be some long term hope that things could get under control eventually.
 
I think replacing an inch or two at each visit is a pretty good idea, but its never that simple, especially with difficult customers. With this particular pool, the only option for adding water is to run a hose from the bathroom faucet across the house to the pool. There was a hose spigot just outside the pool room on the patio, but it froze just after they purchased the house, and rather than fix it, they had it removed. Just about every decision this customer has made was the exact opposite of what should have been done in order to properly maintain this pool. Of course, whenever there is a problem, they immediately point the finger at the guys trying to take care of the pool.

Your assumption would be right about the Bromide bank. To my knowledge, at least 100lbs of Bromine tablets have been added to this pool. Probably more. If I understand the way it works, adding MPS will convert Bromide to Bromine until the MPS is used up, or until the Bromide bank is completely converted to Bomine. So in this case, being that there is an excess of Bromine the MPS would be used up, most likely resulting in high Bromine that would then fall pretty quickly.

If I were to replace enough water to bring the Bromide bank down to the appropriate level such that if all Bromide were converted back to Bromine, I would be at the desired level, I should be able to add excess MPS, which would pretty much just sit there until some of the Bromine is consumed. At that point the MPS would be used up and Bromine would be restored to the desired level. I should be able to maintain a surplus of MPS, which in turn would maintain the Bromine level. Granted, some MPS would be used up oxidizing organics, but that should be easy to address by just adding more MPS each visit. Does this sound right?
 
That all sounds right and should work. MPS will dissipate over time, but I believe that will be noticeably more slowly than bromine in sunlight. So, as long as you can get the bromide bank level down, and thus the DMH level, things should become workable.
 
JasonLion said:
That all sounds right and should work. MPS will dissipate over time, but I believe that will be noticeably more slowly than bromine in sunlight. So, as long as you can get the bromide bank level down, and thus the DMH level, things should become workable.
Click to expand...

I don't think sunlight will be that big of an issue. Its an indoor pool, so the exposure is somewhat limited. The trick will be to find the right amount of MPS to add each visit.

Is there a such thing as too much MPS (obvious exception would be anyone with sensitivity to MPS)?
 
Oxidizers convert bromide to bromine but at different rates. Chlorine is the fastest, ozone is next, and MPS the slowest, but "slowest" still gets used up in hours unless the bromide bank is very low (which it isn't in this case). So for practical purposes using MPS isn't going to help and is more expensive at converting bromide to bromine than adding chlorine.

When you added chlorine at higher levels, it would oxidize chemicals that bromine doesn't handle as well and is probably why you had chloramine smell. Note that MPS does not handle ammonia or inorganic chloramines well and I suspect does not handle inorganic bromamines well either. MPS will oxidize some chemicals that chlorine doesn't do as well and they overlap for some other chemicals so using MPS can reduce but not eliminate chloramine formation when chlorine is used. I don't know how well it would do in a bromine situation, but given that the MPS gets used up due to the bromide bank it's not something where you can maintain a residual of it.

MPS use in indoor pools is for chlorine pools. In that situation there is an MPS residual that helps to oxidize some chemicals thereby reducing some chloramine formation. That principle would not work well in a bromine pool since the MPS would get used up too quickly oxidizing bromide to bromine.

If you can't get the DMH level down through dilution then the other way to keep the water clear is through better coagulation but that can be tricky to do correctly. For commercial/public pools, SeaKlear PRS Stage 1 and 2 is used while for residential pools it's more dicey but GLB® Clear Blue® as shown in this MSDS is PolyDADMAC so a polymeric cationic (positively charged) clarifier (BioGuard® Polysheen Blue is similar). We don't recommend use of these because they are normally not necessary and are tricky to dose and use correctly, but in your situation you may not have a choice without diluting the DMH from the water.
 

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply