I have a Baja Spa hot tub that has the tablet dispenser located inside the filter. I load this up with about 5-6 tablets and let it automatically release them. So how do I maintain/regulate my FC with this system? I realize this may seem like a really simple question but I’m new here and just learning about spas and water balance. The local Leslie’s pool store just tells me to add a cupful of their Fresh and Clear product after every use. And that’s all I need to do. Help please.
Not sure how to adjust FC levels with tablets
- Thread starter dooger54
- Start date
- May 23, 2015
- 24,381
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Are you running this as a bromine hot tub or a chlorine hot tub?
One does not usually use trichlor tablets in a hot tub as they are too acidic and dissolve too quickly. I suspect that tablet feeder is designed for bromine tablets which dissolve more slowly.
Please read this post -
How do I use Chlorine in my Spa (or pool)?
One does not usually use trichlor tablets in a hot tub as they are too acidic and dissolve too quickly. I suspect that tablet feeder is designed for bromine tablets which dissolve more slowly.
Please read this post -
How do I use Chlorine in my Spa (or pool)?
I did read that post. I am using Bromine tablets and running as a bromine hot tub.
- May 23, 2015
- 24,381
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Have both the Basic OTO which shows colors for bromine and the Taylor K-2006 for my pool.
And yes, I understand FC stands for free chlorine.
- May 23, 2015
- 24,381
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
If you have a bromine tub and you have a sufficient bromide bank built up, then you really don’t need to use tablets. Bromine tablets, like trichlor, are acidic and they add DMH to your tub water which has a similar effect on active bromine levels as CYA has with chlorine. Too much DMH in a tub can cause overstabimization and sanitation problems.
Does that tablet feeder have a way of adjusting the dissolution rate? Floater type feeders have an adjustable opening to limit the dissolution rate.
Does that tablet feeder have a way of adjusting the dissolution rate? Floater type feeders have an adjustable opening to limit the dissolution rate.
You don't have FC in a bromine spa, so you can't adjust it. When you add bromine to a spa, originally you have hypobromous acid (HOBr), your active sanitizer, which after it is used up oxidizing waste, ends being just a bromide ion (Br-), also referred to as a bromide bank. When you add chlorine, ozone, or MPS, they oxidize the bromide ion back into hypobromous acid. Normally, in a chlorine pool, the chlorine or MPS will oxidize waste, but when there's bromide ions, it oxidizes them instead. So when you add chlorine, it oxidizes immediately to "refresh" your bromine, and you don't have (nor test for) FC in a bromine pool. Read pages 28-31 of your Taylor K2006 test kit instructions.
yes, there is a small adjustment available on the feeder. It has holes that can be partially closed, but there a only four and they are only about 1/4 long. I can also adjust the times the tub runs the filter cycle. It is factory set at 4 hours twice a day.
I will read the noted pages in my Taylor manual.
- May 23, 2015
- 24,381
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Your Taylor kit is fine for measuring bromine. The scaling factor for each drop of the titrating reagent is different. The testing methods used are sensitive to ALL OXIDIZING HALOGENS, they are not specific to any particular halogen. So the DPD indicator reacts with chlorine and bromine in the same way - the dye is oxidized from its clear form to a pink form. MPS is a little different because it does not react with the DPD dye, but rather the titrating drops. Taylor sells a set of reagents that can be used to remove MPS interference.
Finally, your testing is sensitive to TOTAL BROMINE ONLY. The DPD-FAS test can not distinguish free bromine from combine bromine and so the test measures total bromine. That’s ok though because bromamines are sanitizing chemicals as well though definitely not something you want in high concentrations. As long as you regenerate the bromide into bromine, you should be fine.
MPS can reactivate spent bromide BUT it is much slower than just using chlorine to do it. The MPS will partially oxidize the bromide and any organics in the tub so it’s generally not a preferred method for increasing bromine levels.
Finally, your testing is sensitive to TOTAL BROMINE ONLY. The DPD-FAS test can not distinguish free bromine from combine bromine and so the test measures total bromine. That’s ok though because bromamines are sanitizing chemicals as well though definitely not something you want in high concentrations. As long as you regenerate the bromide into bromine, you should be fine.
MPS can reactivate spent bromide BUT it is much slower than just using chlorine to do it. The MPS will partially oxidize the bromide and any organics in the tub so it’s generally not a preferred method for increasing bromine levels.
So using my K-2006 kit here are my numbers-
Total bromine- 2.0
TA - 50
CH - 160
Suggestions? Again, all I am doing is using the bromine tablet feeder and adding a capful of Leslie’s Fresh n Clear after every use. Should I be adding a cup of bleach every week? My tub is 250 gals.
Total bromine- 2.0
TA - 50
CH - 160
Suggestions? Again, all I am doing is using the bromine tablet feeder and adding a capful of Leslie’s Fresh n Clear after every use. Should I be adding a cup of bleach every week? My tub is 250 gals.
- May 23, 2015
- 24,381
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
What’s your pH? I would not be using the Fresh’n’Clear thatvregukarly as it is MPS and acidic. Between that and the tablets, you could drop your TA to zero accidentally and cause your pH to crash.
Using bleach after a soak will oxidize bather waste and regenerate the bromine in your tub. You total bromine is too low. It should be between 4-6ppm for a hot tub.
How did you get 2ppm? How many drops of the R-0871 did you use and what was the test volume (10mL or 25mL)?
Using bleach after a soak will oxidize bather waste and regenerate the bromine in your tub. You total bromine is too low. It should be between 4-6ppm for a hot tub.
How did you get 2ppm? How many drops of the R-0871 did you use and what was the test volume (10mL or 25mL)?
Used 10ml volume and took 4 drops R-0871 to get clear.
My Ph is right at 7.4. It was low and I had to bring it up using soda ash.
I will quit using the Fresh n Clear and start using bleach. Added a cup tonight. I will recheck all numbers tomorrow.
My TA was only 10 two days ago and have been working on getting that up too. Now at about 50.
So I just finished reading the entire 7 pages of the “How to use bromine in my spa”. When I did my test for chlorine using my Taylor test kit it cam back as 2ppm. It seems like I need to multiply this by 2.25 to get my bromine level? So using this my bromine level is 4.5, which is about right.
Do I have this correct?
Do I have this correct?
I think so. The bromine sticky is nowhere near as clear and consise as the chlorine one, which is why I decided to go clorine when I got my first hot tub two and a half weeks ago. It wasn't until I read the Taylor test kit instructions (after I read the bromine thread) that I understood what was going on with bromine.
- May 23, 2015
- 24,381
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
That’s why I asked you about drop count and sample volume, it sounded too low to me. Yes, your total Br level is 4.5ppm. Your right at the minimum.
Definitely cease the daily MPS. The build up of sulfates in the water is not good for your heater. You can use it for shocking once per week.
You might also consider getting the Taylor K-2106 test kit exclusively for your hot tub. The R-0872 drops are FAS titrating reagent just as the R-0871 drops but a slightly different concentration so that the Bromine numbers are round numbers. It’s designed for a bromine hotbtub. Your choice, of course...
- - - Updated - - -
Oh, and one other thing. Definitely heed the advice in the sticky and dump your hot tub water regularly every 3 months. The slow build up of bromates over time is not healthy and there’s no way to get rid of them except through water exchange. At that point you can also do a plumbing purge with Ahh-some hot tub cleaner to get any biofilms out of the plumbing. It’s good to purge the tub at least once a year, or twice per year if the tub is heavily used.
So I just re-tested after adding a cup of bleach last night. Bromine now down to 2.25 and Ph over 8.0. What gives?
- May 23, 2015
- 24,381
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Without any jets running (just have the water at standby temp with the recirculation pump running), can you please post a full set of test results - total bromine, pH, TA and CH.
Here they are, but probably skewed. I freaked out when the bromine was so low and Ph high so added about 3 ounces of Fresh n Clear about two hours ago-
Ph - 7.6
Ch - 170
TA - 50
Bromines - 16.7 (7.5 Chlorine)
- May 23, 2015
- 24,381
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
The MPS is interfering with your results. The MPS consumes some of the R-0871 and so it makes your total bromine look higher than it really is. Your bromine has probably always been low and the daily MPS has been masking it. MPS will convert bromide to bromine but not as quickly as chlorine does. The MPS is also acidic and suppressing your TA and holding your pH down due to its acidity.
My suggestion is that you get off the MPS for now and try to get your tub balanced just using bleach and acid (muriatic acid) to control pH. You may need to raise your TA a bit more with baking soda (perhaps to 60ppm or so) to be safe. The pH rise you see is normal because the tub aeration raises pH by outgassing of CO2.
My suggestion is that you get off the MPS for now and try to get your tub balanced just using bleach and acid (muriatic acid) to control pH. You may need to raise your TA a bit more with baking soda (perhaps to 60ppm or so) to be safe. The pH rise you see is normal because the tub aeration raises pH by outgassing of CO2.
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