Jump to content

I Need Help!


Recommended Posts

with a TA of greater than 250 there is a lot of outgassing of CO2 which is causing the pH rise. It is the aeration of your jets and bubblers combined with the very high TA causeing the pH rise.blink.gif

Perhaps this will explain it for you.

The BEST way to get your bromine levels up after a fill and drain is to add sodium bromide and then oxidizing and then adding the floater. This is called three step bromine and is the easiest way to do bromine, IMHO. Here is a step by step to get you started.smile.gif

I read your post about TA and pH and it made my eyeballs go :wacko: A little over my head! :lol:

There is sooo much information and help here I really appreciate it. I will do the 3 step bromine method at my next fill. So can you please tell me if this "plan" will work for my situation.

1. Use spa flush product

2. Drain, clean and fill

3. Add Sodium Bromide

4. Shock (should this be chlorine or non-chlorine based?)

5. Add floater

6. Adjust TA

7. Adjust pH

8. Add calcium booster (my fill water has no calcium)

Or should I adjust TA and pH, then sodium bromide, shock and oxidize? Does it really matter? I just want to make sure I get some sanitizer going in it.

Today I used my Taylor kit and keep getting a pH of around 7.9-8.0 and TA of 100

I cannot seem to get my pH lower. The other day I added just a tiny bit of acid to move it down a little because my TA was 120, ph 7.9 and it dropped the pH down in the 6 range and TA around 40.

I just cannot seem to get it right :( My family is visiting for the week and I have been keeping bromide up and everything in somewhat normal ranges to enjoy it while they are here. I plan to drain it next week and try to start over.

Also, the water smells funny when I open the cover. Does bromine have a unique smell to it? Could it be my ozone system. The water is clear and sanitizer is fine...it seems that since switching to bromine it smells funny. Any ideas?

Re read the step by step for 3 step bromine and follow it step by step. If you do you will adjust CH, TA, and pH BEFORE you add sodium bromide and heat the spa.

Link to comment
Share on other sites

  • Replies 52
  • Created
  • Last Reply

Top Posters In This Topic

with a TA of greater than 250 there is a lot of outgassing of CO2 which is causing the pH rise. It is the aeration of your jets and bubblers combined with the very high TA causeing the pH rise.blink.gif

Perhaps this will explain it for you.

The BEST way to get your bromine levels up after a fill and drain is to add sodium bromide and then oxidizing and then adding the floater. This is called three step bromine and is the easiest way to do bromine, IMHO. Here is a step by step to get you started.smile.gif

I read your post about TA and pH and it made my eyeballs go :wacko: A little over my head! :lol:

There is sooo much information and help here I really appreciate it. I will do the 3 step bromine method at my next fill. So can you please tell me if this "plan" will work for my situation.

1. Use spa flush product

2. Drain, clean and fill

3. Add Sodium Bromide

4. Shock (should this be chlorine or non-chlorine based?)

5. Add floater

6. Adjust TA

7. Adjust pH

8. Add calcium booster (my fill water has no calcium)

Or should I adjust TA and pH, then sodium bromide, shock and oxidize? Does it really matter? I just want to make sure I get some sanitizer going in it.

Today I used my Taylor kit and keep getting a pH of around 7.9-8.0 and TA of 100

I cannot seem to get my pH lower. The other day I added just a tiny bit of acid to move it down a little because my TA was 120, ph 7.9 and it dropped the pH down in the 6 range and TA around 40.

I just cannot seem to get it right :( My family is visiting for the week and I have been keeping bromide up and everything in somewhat normal ranges to enjoy it while they are here. I plan to drain it next week and try to start over.

Also, the water smells funny when I open the cover. Does bromine have a unique smell to it? Could it be my ozone system. The water is clear and sanitizer is fine...it seems that since switching to bromine it smells funny. Any ideas?

Re read the step by step for 3 step bromine and follow it step by step. If you do you will adjust CH, TA, and pH BEFORE you add sodium bromide and heat the spa.

The smell you are smelling is most likely either bromamines ('fishy'), bromine (chemical), or ozone (acrid). Since it dissipates after you open the cover I suspect it's ozone.

Chlorine destroys ozone and vice versa. Ozone activates bromide into bromine sanitizer.

Link to comment
Share on other sites

with a TA of greater than 250 there is a lot of outgassing of CO2 which is causing the pH rise. It is the aeration of your jets and bubblers combined with the very high TA causeing the pH rise.blink.gif

Perhaps this will explain it for you.

The BEST way to get your bromine levels up after a fill and drain is to add sodium bromide and then oxidizing and then adding the floater. This is called three step bromine and is the easiest way to do bromine, IMHO. Here is a step by step to get you started.smile.gif

I read your post about TA and pH and it made my eyeballs go :wacko: A little over my head! :lol:

There is sooo much information and help here I really appreciate it. I will do the 3 step bromine method at my next fill. So can you please tell me if this "plan" will work for my situation.

1. Use spa flush product

2. Drain, clean and fill

3. Add Sodium Bromide

4. Shock (should this be chlorine or non-chlorine based?)

5. Add floater

6. Adjust TA

7. Adjust pH

8. Add calcium booster (my fill water has no calcium)

Or should I adjust TA and pH, then sodium bromide, shock and oxidize? Does it really matter? I just want to make sure I get some sanitizer going in it.

Today I used my Taylor kit and keep getting a pH of around 7.9-8.0 and TA of 100

I cannot seem to get my pH lower. The other day I added just a tiny bit of acid to move it down a little because my TA was 120, ph 7.9 and it dropped the pH down in the 6 range and TA around 40.

I just cannot seem to get it right :( My family is visiting for the week and I have been keeping bromide up and everything in somewhat normal ranges to enjoy it while they are here. I plan to drain it next week and try to start over.

Also, the water smells funny when I open the cover. Does bromine have a unique smell to it? Could it be my ozone system. The water is clear and sanitizer is fine...it seems that since switching to bromine it smells funny. Any ideas?

Re read the step by step for 3 step bromine and follow it step by step. If you do you will adjust CH, TA, and pH BEFORE you add sodium bromide and heat the spa.

The smell you are smelling is most likely either bromamines ('fishy'), bromine (chemical), or ozone (acrid). Since it dissipates after you open the cover I suspect it's ozone.

Chlorine destroys ozone and vice versa. Ozone activates bromide into bromine sanitizer.

Thank you. I will print and follow the directions step by step. If I can catch the TA and pH from the start, maybe the pH will not skyrocket again.

Again, I appreciate all of your help :)

Link to comment
Share on other sites

Thank you. I will print and follow the directions step by step. If I can catch the TA and pH from the start, maybe the pH will not skyrocket again.

Again, I appreciate all of your help :)

THAT is the idea. Get the TA in line and you won't have pH stability problems. Think of TA as the amount of carbonation in your spa (It is--it's a measure of the amount of bicarbonate ions). This carbonation is constantly driving your pH up to around 8.2. Lower the TA and you lower the amount of bicarbonate in the water. Lower the bicarbonate and you lower the tendency for the pH to climb to 8.2. Aeration speeds up the pH rise. We aereate hot tubs a lot so pH rise becomes a problem when the TA is high.

Your first step is to lower the TA. This is how:

1. Add acid to lower your PH to between 7.0 and 7.2 (this also lowers TA) then test your TA

2. Aerate until PH rises to around 7.6 (the only way to raise PH without also raising TA)

Repeat steps 1 and 2 until you reach the desired TA.

This post gives more detailed instruction and applies to both pools and spas. It might seem long but most of it is explanation as to why it works and suggestions on how to aerate the water. The actual procedure is in blue at the end. Read it.

Here is Nitro's write up on lowering TA in a hot tub. Read it.

Also, since you are running bromine remember that bromine is effective in a pH range of 7.2 to 8.0 so, as long as your pH remaims below 8.0 you are fine and that bromine tabs are slightly acidic so you want your target TA a bit higher than if you were using chlorine (dichlor/bleach) so shoot for a target TA of around 100 ppm (up to 120 ppm) and see how your pH stability is. If your pH is still going too high too fast then drop the TA a bit more. pH is never going to remain stable in a hot tub because of the amount of aeration but it should not need to be adjusted on a daily basis.

Link to comment
Share on other sites

OK Here is where I am at..... Advice appreciated!

-I used the spa flush

-Drained water, cleaned and refilled

-Fill water was pH 7.6, TA 350 and CH 0 based on my taylor kit results

- I added Sodium Bromide, shocked with Leisure time RENEW

- Added floater

- I then let the water sit at temp of 62 degrees all night without heating since it got late

Today

- Turned spa on and its heating up

-Water tested pH 8.0+ and TA 350 (I am assuming the pH jumped because of the bromine and shock?)

- Followed the instructions on lowering TA

Test, aerate, test, acid, aerate, test...... It took about 4+ hours and about 8+ tests of pH and TA to get to this result....

Current water:

Temp 72 degrees

pH about 7.8-8.0 (hard to tell with taylor kit...but one drop of acid demand test would bring it down to 7.6 So, I am assuming the pH is closer to 7.8, right?)

TA 60

Now, is the TA ok this low??? I know all companies state a TA of 80-120 is best...should I increase it with baking soda? I do have Alk increaser but that increases pH too, right? Will be adding Calcium increaser in a few hours. I need a break ;)

How are my numbers looking? The instructions and ease of lowering TA along with pH was outstanding! I love the procedure and thought it looked confusing at first, but it was so easy and awesome! Thanks for any advice :)

Link to comment
Share on other sites

Hi bromine readings (you just shocked all the sodium bromide into active bromine) can give a false high PH reading. Sodium bromide and renew should not of raised the PH, and since the tub was not running overnight, airation did not raise it. What was your bromine reading at that time.

Link to comment
Share on other sites

Hi bromine readings (you just shocked all the sodium bromide into active bromine) can give a false high PH reading. Sodium bromide and renew should not of raised the PH, and since the tub was not running overnight, airation did not raise it. What was your bromine reading at that time.

Lower TA is fine if its what your tub needs to keep the PH down. baking soda is Alk. increaser, and as a note, calcium hardness increaser may raise the PH and ALK also, I personally do the calcium hardness first, I always do PH/ALK last because the other chemicals will effect it. I wouls also suggest you read the other topics above about PH/ ALK ect. so you have an understanding on how they work and what they are.

Link to comment
Share on other sites

Well, I thought I was on the right track.... :(

I was told to do bromide, shock first...so I think you are right about it raising the pH when the tub sat cold all night.

I didn't know I needed to do Calcium first. My current readings are: pH somewhere around 7.9-8.0 (1 drop acid demand brings it to around 7.7-7.8)

TA 60

CH 60

temp 97

Bromine 18

What should I do? Should I go ahead and continue putting in my Calcium hardness increaser and let the bromine levels fall by keeping the cover off and then go from there.

Should I increase my TA if the calcium increaser doesn't increase it?

Link to comment
Share on other sites

Well, I thought I was on the right track.... :(

I was told to do bromide, shock first...so I think you are right about it raising the pH when the tub sat cold all night.

RTFM

I didn't know I needed to do Calcium first. My current readings are: pH somewhere around 7.9-8.0 (1 drop acid demand brings it to around 7.7-7.8)

TA 60

CH 60

temp 97

Bromine 18

What should I do? Should I go ahead and continue putting in my Calcium hardness increaser and let the bromine levels fall by keeping the cover off and then go from there.

I would.

Should I increase my TA if the calcium increaser doesn't increase it?

It won't, Calcium increaser increases CALCIUM. TA increaser (which is simply baking soda--read the label and it will say either sodium bicarbonate or sodium hydrogen carbonate which are other names for baking soda) increases TA. it ain't rocket science

Leave the TA alone right now. Get the calcium in line if it is below about 130 ppm. If it is higher don't worry about it. DO NOT TRY AND ADJUST OR TEST pH UNTIL THE BROMINE IS BELOW 10 PPM.

Link to comment
Share on other sites

OK Here is where I am at..... Advice appreciated!

-I used the spa flush

-Drained water, cleaned and refilled

-Fill water was pH 7.6, TA 350 and CH 0 based on my taylor kit results

- I added Sodium Bromide, shocked with Leisure time RENEW

- Added floater

- I then let the water sit at temp of 62 degrees all night without heating since it got late

Today

- Turned spa on and its heating up

-Water tested pH 8.0+ and TA 350 (I am assuming the pH jumped because of the bromine and shock?)

- Followed the instructions on lowering TA

Test, aerate, test, acid, aerate, test...... It took about 4+ hours and about 8+ tests of pH and TA to get to this result....

Current water:

Temp 72 degrees

pH about 7.8-8.0 (hard to tell with taylor kit...but one drop of acid demand test would bring it down to 7.6 So, I am assuming the pH is closer to 7.8, right?)

TA 60

Now, is the TA ok this low??? I know all companies state a TA of 80-120 is best...should I increase it with baking soda? I do have Alk increaser but that increases pH too, right? Will be adding Calcium increaser in a few hours. I need a break ;)

How are my numbers looking? The instructions and ease of lowering TA along with pH was outstanding! I love the procedure and thought it looked confusing at first, but it was so easy and awesome! Thanks for any advice :)

TA is fine for now at 60 ppm. Test it weekly and when it drops to 50 ppm use baking soda or alk increaser to bring it back up, they are EXACTLY THE SAME THING EXCEPT FOR THE PRICE AND PURITY. Baking soda is cheaper and purer than the sodium bicarbonate packaged as alk increaser or TA increaser and both have exactly the same effect on pH..they raise it!

Remember, bromine is not as picky about pH as chlorine is so if your pH is below 8.0 you are fine (don't let it go below 7.2 for normal soaking). If the pH rises too fast without adding any chems and your sanitizer is below 10 ppm that generally means the TA is too high and should be lowered. IF the pH crashes too low when you add bromine or MPS or just from use and you need to chemically raise it regularly that generally means that you are keeping the TA too low.

Link to comment
Share on other sites

Thanks for the replies.

I did increase the CH more today. I am having trouble with the Taylor CH test. After adding all the drops it doesn't turn pink and then eventually blue. I KNOW the CH is present and is around 150-180 now so why do you think my test cannot detect it? Is that possible?

So once my bromine level gets under 10 I will test pH and TA and adjust. It seems like the pH is around 7.7-7.8. Could the pH crash too low once the bromine levels decrease? Could I be in the opposite situation now needing to increase pH/TA?

What should I do next time? I know I was told to get the bromide and shock into the water asap to fend off bacteria, but if the high bromine levels are messing with my pH what is the correct order to do this?

Should calcium always be adjusted first, before pH/TA?

Should I always wait to balance water until bromine is below 10?

Sorry for all the questions. I seem to get conflicting answers on methods of doing this. I just want to do it right the first time and every time!

Link to comment
Share on other sites

Well, I thought I was on the right track.... :(

I was told to do bromide, shock first...so I think you are right about it raising the pH when the tub sat cold all night.

RTFM

I didn't know I needed to do Calcium first. My current readings are: pH somewhere around 7.9-8.0 (1 drop acid demand brings it to around 7.7-7.8)

TA 60

CH 60

temp 97

Bromine 18

What should I do? Should I go ahead and continue putting in my Calcium hardness increaser and let the bromine levels fall by keeping the cover off and then go from there.

I would.

Should I increase my TA if the calcium increaser doesn't increase it?

It won't, Calcium increaser increases CALCIUM. TA increaser (which is simply baking soda--read the label and it will say either sodium bicarbonate or sodium hydrogen carbonate which are other names for baking soda) increases TA. it ain't rocket science

Leave the TA alone right now. Get the calcium in line if it is below about 130 ppm. If it is higher don't worry about it. DO NOT TRY AND ADJUST OR TEST pH UNTIL THE BROMINE IS BELOW 10 PPM.

Well, I am sorry I offended you. The previous response to me about my calcium increaser said that it may increase my pH/TA. That is why I asked. It may not be rocket science to YOU because you obviously know everything about hot tubs... Everyone has their own opinions and methods of doing things and I am getting so much differing advice that I am confused.

Link to comment
Share on other sites

Well, I am sorry I offended you. The previous response to me about my calcium increaser said that it may increase my pH/TA. That is why I asked. It may not be rocket science to YOU because you obviously know everything about hot tubs... Everyone has their own opinions and methods of doing things and I am getting so much differing advice that I am confused.

RTFM

It tells you what to do step by step and it is not rocket science nor is it opinion. It's easier than baking a cake from scratch! If you follow the steps it's very easy. If you do things out of order it gets more complicated which is why I said to RTFM.

Also, calcium hardness increaser is calcium chloride and will not raise TA or pH any more than table salt (sodium chloride) will. If your calcium increaser is not calcium chloride then it is not a standard calcium hardness increaser and I would not use it. It might be a cheaper, less pure mix with non soluble calcium carbonate (chalk) and/or caustic calcium hydroxide (lime) neither of which are desirable to use. Learn your ingredients and know your labels is the best advice i can give you.

Link to comment
Share on other sites

Well, I am sorry I offended you. The previous response to me about my calcium increaser said that it may increase my pH/TA. That is why I asked. It may not be rocket science to YOU because you obviously know everything about hot tubs... Everyone has their own opinions and methods of doing things and I am getting so much differing advice that I am confused.

RTFM

It tells you what to do step by step and it is not rocket science. It's easier than baking a cake from scratch! If you follow the steps it's very easy. If you do things out of order it gets more complicated which is why I said to RTFM.

I have read it and will print it.

The reason why I am confused is because if you read back I was told by another respected board member to do the sanitizer first.

I will stop asking questions now and just figure it out. After all, I could bake a cake with my eyes closed.

Link to comment
Share on other sites

After all, I could bake a cake with my eyes closed.

I bet your wouldn't cream the flour and butter together and then sift in the sugar and then bake it and then try to grease the pan and try to add the eggs and vanilla after it comes out of the oven, would you?smile.gif

no, you would cream the butter and sugar, add the eggs and vanilla, sift in the flour, grease the pans, and then bake the batter!

My point simply was that you were taking something that really is no harder than baking a cake (actually I would have to say it's a bit easier) and making it more difficult than it needs to be. You have a recipe that many people have successfully followed on how to do 3 step bromine (and it's not my recipe either!) and if you just follow it step by step all will be good.

Link to comment
Share on other sites

I think I was the one who suggested adding sanitizer right away just so there wouldn't be any chance of bacteria growing, but I didn't think it was going to get that high since only some was needed to prevent such bacteria growth. Sorry I confused the situation. There's no disaster here. NavyChick, you're doing fine and nothing you did is that much of a problem. The sanitizer level will drop if you don't add any oxidizer and keep the bromine floater out until the bromine gets lower. Then the pH test will become valid though I believe it will be valid below 22 ppm bromine (10 ppm chlorine).

When one increases the CH is also not a big deal. It's mostly increased to reduce the chance of foaming.

The most frustrating part is that since you have such high TA in your fill water, you have that long acid, aerate sequence to lower the TA, but the benefit of doing that is that your pH will be more stable going forward.

waterbear, in the bromine instructions the first step adjusts the TA, then pH and then CH before the second step adds sodium bromide and the third step shocks the spa to create bromine. In cases like this one where the TA is very high, it can take a while to get the TA, pH and CH adjusted (especially the TA). Though I understand why one wouldn't want to get to shock levels that would invalidate the pH, wouldn't it be OK to start off adding sodium bromide and a small amount of oxidizer to get to 5-10 ppm bromine just to keep the water from potentially going south? Also, the pH test tolerates up to around 10 ppm chlorine so that should be equivalent to around 22 ppm bromine, not 10 ppm bromine, right? So the pH reading NavyChick has been seeing is probably not invalid, right?

Link to comment
Share on other sites

I think I was the one who suggested adding sanitizer right away just so there wouldn't be any chance of bacteria growing, but I didn't think it was going to get that high since only some was needed to prevent such bacteria growth. Sorry I confused the situation. There's no disaster here. NavyChick, you're doing fine and nothing you did is that much of a problem. The sanitizer level will drop if you don't add any oxidizer and keep the bromine floater out until the bromine gets lower. Then the pH test will become valid though I believe it will be valid below 22 ppm bromine (10 ppm chlorine).

When one increases the CH is also not a big deal. It's mostly increased to reduce the chance of foaming.

The most frustrating part is that since you have such high TA in your fill water, you have that long acid, aerate sequence to lower the TA, but the benefit of doing that is that your pH will be more stable going forward.

waterbear, in the bromine instructions the first step adjusts the TA, then pH and then CH before the second step adds sodium bromide and the third step shocks the spa to create bromine. In cases like this one where the TA is very high, it can take a while to get the TA, pH and CH adjusted (especially the TA). Though I understand why one wouldn't want to get to shock levels that would invalidate the pH, wouldn't it be OK to start off adding sodium bromide and a small amount of oxidizer to get to 5-10 ppm bromine just to keep the water from potentially going south? Also, the pH test tolerates up to around 10 ppm chlorine so that should be equivalent to around 22 ppm bromine, not 10 ppm bromine, right? So the pH reading NavyChick has been seeing is probably not invalid, right?

Thank you :) Today my readings are:

temp 103

pH 7.8-8.0 stable

TA 60 stable

Bromine 13.5 coming down

CH somewhere between 150-250

I am having trouble reading CH from the taylor kit. The water barely turns pink and never turns blue. CH reading is from the strips I had. I am going to take a sample to my local spa store for a reading.

I used the chlorine test to test for bromine. It took 12 drops at 10mL (12 x 1.125 = 13.5)

Link to comment
Share on other sites

waterbear, in the bromine instructions the first step adjusts the TA, then pH and then CH before the second step adds sodium bromide and the third step shocks the spa to create bromine. In cases like this one where the TA is very high, it can take a while to get the TA, pH and CH adjusted (especially the TA). Though I understand why one wouldn't want to get to shock levels that would invalidate the pH, wouldn't it be OK to start off adding sodium bromide and a small amount of oxidizer to get to 5-10 ppm bromine just to keep the water from potentially going south?

Even very high TA (300 ppm) in a tub can normally be adjusted down to an acceptable range (100-120 ppm) in a day or less in the small volume of water in a tub given the excellent aeration built in. If there is any questions I would just add enough bleach to bring the FC up to about 5 ppm a few hours into the process if it is taking a long time. The tub is not heated yet since heating will not have any significant effect on TA or CH. I would hold off on the sodium bromide and oxidizer and bromine tabs until the water balance is complete. The spa can always be shocked with bleach to a high level before any sodium bromide is added to decontaminate but it should not be necessary, IMHO.

Also, the pH test tolerates up to around 10 ppm chlorine so that should be equivalent to around 22 ppm bromine, not 10 ppm bromine, right? So the pH reading NavyChick has been seeing is probably not invalid, right?

The phenol red is not converting to chlorophenol red in this case but rather to bromophenol red (pH range 5.2 to 5.8 and color change from yellow to red) and bromophenol blue (pH range 3.0 to 4.6 and color change from yellow to the characteristic purple-blue color that is not on the comparator commonly seen when testing pH in bromine systems when the bromine levels are high) so you either get a false high pH reading or a color that is not even on the comparator when testing with high bromine levels. According to Taylor Technologies' published data the purple blue color develops at around 10 ppm. bromine.

Link to comment
Share on other sites

I am having trouble reading CH from the taylor kit. The water barely turns pink and never turns blue. CH reading is from the strips I had. I am going to take a sample to my local spa store for a reading.

I used the chlorine test to test for bromine. It took 12 drops at 10mL (12 x 1.125 = 13.5)

1) your high bromine levels are probably bleaching out the test. Try doing the test with a 10 ml sample as the instructions in the lid of the test kit give as an alternative for high calcium levels and see what you get. The colors are a bit more intense when done this way. When the sanitizer is in normal range the test will be easier to read. Even at normal sanitizer levels the colors are on the pastel side and not really vibrant like the other tests. The color change is from a pale pink to a light sky blue. Once again, this is why doing things in the listed order is easier.

2) strips do not test calcium hardness but rather total (calcium and magnesium) hardness so it is not really valid for spa and pool water testing.

Link to comment
Share on other sites

Thanks for the suggestion of just adding some chlorine (i.e. bleach) if there is any concern about disinfection to start with. Yes, that's simpler than getting to the bromide/oxidizer steps and won't risk getting too high to foul up pH tests.

According to Taylor Technologies' published data the purple blue color develops at around 10 ppm. bromine.

Yes, I've read the same thing in the chlorine Taylor kit where they say the following:

FALSE READINGS: high levels of chlorine (usually > 10 ppm) will quickly and completely convert phenol red into another pH indicator (chlorphenol red). This new indicator is a dark purple when the water's pH is above 6.6. Unfortunately, some pool operators mistake the purple color for dark red and think the pool water is very alkaline and wrongly add acid to the pool.

When a sanitizer level is not extreme, only some of the phenol red may convert to chlorphenol red. However, purple + orange (for example, pH 7.4) = red. This error is more subtle as no purple color is observed and the operator does not suspect that a false high pH reading has been produced. Some operators neutralize the sanitizer first by adding a drop of chlorine neutralizer (i.e. sodium thiosulfate). However, thiosulfate solutions have a high pH and, if heavily used, may cause a false higher sample pH.

For the K-2106 test kit, Taylor lists Potential Interferences for pH as follows:

Sanitizer levels > approx. 10 ppm may cause a blue-purple color resulting in false high readings. Wait for sanitizer level to decrease to normal levels and retest to assure an accurate reading.

However, 10 ppm chlorine is 22.5 ppm bromine and the chlorine neutralizers in the pH test operate on a molar basis and the amount of dye oxidized by any leftover oxidizer would also be on a molar basis. So I believe Taylor is wrong when they say that the pH test may be invalid above 10 ppm bromine -- it's 10 ppm chlorine so should be 22.5 ppm bromine. I'll E-mail them to ask about this and will update y'all with what I find out.

Link to comment
Share on other sites

Thanks for the suggestion of just adding some chlorine (i.e. bleach) if there is any concern about disinfection to start with. Yes, that's simpler than getting to the bromide/oxidizer steps and won't risk getting too high to foul up pH tests.

According to Taylor Technologies' published data the purple blue color develops at around 10 ppm. bromine.

Yes, I've read the same thing in the chlorine Taylor kit where they say the following:

FALSE READINGS: high levels of chlorine (usually > 10 ppm) will quickly and completely convert phenol red into another pH indicator (chlorphenol red). This new indicator is a dark purple when the water's pH is above 6.6. Unfortunately, some pool operators mistake the purple color for dark red and think the pool water is very alkaline and wrongly add acid to the pool.

When a sanitizer level is not extreme, only some of the phenol red may convert to chlorphenol red. However, purple + orange (for example, pH 7.4) = red. This error is more subtle as no purple color is observed and the operator does not suspect that a false high pH reading has been produced. Some operators neutralize the sanitizer first by adding a drop of chlorine neutralizer (i.e. sodium thiosulfate). However, thiosulfate solutions have a high pH and, if heavily used, may cause a false higher sample pH.

However, 10 ppm chlorine is 22.5 ppm bromine and the chlorine neutralizers in the pH test operate on a molar basis and the amount of dye oxidized by any leftover oxidizer would also be on a molar basis. So I believe Taylor is wrong when they say that the pH test may be invalid above 10 ppm bromine -- it's 10 ppm chlorine. I'll E-mail them to ask about this and will update y'all with what I find out.

They state specifially about bromine when it is over 10 ppm also. I do not know the conversion rate of phenol red to bromophenol red and/or bromophenol blue but anyone who has ever tested pH in a bromine spa and seen the purple blue color that does not match any of the colors on the comparator knows what bromophenol blue looks like at a pH above 4.6! I have seen this happen first hand at bromine levels that were only at about 6 ppm and the same pH test (not Taylor's btw) worked in a chlorine system properly at 10 ppm FC (by properly I mean that it did not develop the blue-purple color but still had colors that matched the comparator). IF you have never tested pH in a bromine system them you have not seen this phenomenon.

Link to comment
Share on other sites

I just did another test after leaving the cover off over an hour. Bromine is 9 ppm, pH still around 7.8-8.0, TA 60 and CH is at 375

So now that I am under 9 ppm, does that mean that my pH and TA are valid?

I tested bromine twice to make sure...using both the 10mL and 25mL sample sizes.

Link to comment
Share on other sites

IF you have never tested pH in a bromine system them you have not seen this phenomenon.

OK. By the way, one way to test the pH when the sanitizer level is high is to dilute with distilled water, but the water must be distilled or deionized since it must be unbuffered. Then, doing a dilution will cut down the sanitizer level with no measurable difference in pH due to the sample being buffered (with an unbuffered sample, doing a 50% dilution would change the pH by 0.3 towards neutral 7.0, but with a buffered sample the change when diluting with unbuffered water is so small as to not be measurable).

Link to comment
Share on other sites

I just did another test after leaving the cover off over an hour. Bromine is 9 ppm, pH still around 7.8-8.0, TA 60 and CH is at 375

So now that I am under 9 ppm, does that mean that my pH and TA are valid?

yepsmile.gif

I tested bromine twice to make sure...using both the 10mL and 25mL sample sizes.

Your calcium is fine but you don't want it to go any higher, btw.

I assume you redid the calcium test with the 10 ml sample and it changed to blue at 15 drops. With the 10 ml sample you would need 37-38 drops to see the color change and I suspect you didn't go that far and that is why it did not change color for you.

Link to comment
Share on other sites

I just did another test after leaving the cover off over an hour. Bromine is 9 ppm, pH still around 7.8-8.0, TA 60 and CH is at 375

So now that I am under 9 ppm, does that mean that my pH and TA are valid?

yepsmile.gif

I tested bromine twice to make sure...using both the 10mL and 25mL sample sizes.

Your calcium is fine but you don't want it to go any higher, btw.

I assume you redid the calcium test with the 10 ml sample and it changed to blue at 15 drops. With the 10 ml sample you would need 37-38 drops to see the color change and I suspect you didn't go that far and that is why it did not change color for you.

I know I don't want the calcium to go any higher. I did the CH test before with a 25 ml sample and yes, kinda gave up beyond 25 drops. I redid the test using a 10 ml sample and it took 15 drops x 25 ml= 375. The color with the 25 ml sample just wasn't pink and it was kinda impossible to read. The 10 ml sample did the trick. Thanks for the advice!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...



×
×
  • Create New...