Top Off Water Balance Routine

[diggerdan4]

So we have had our tub for two months now and last night opened cover and found it to be very cloudy. Two days prior it was perfectly clear! I added 3 TBS of MPS hoping this would clear it up and came out 10 minutes later to check on tub and was over flowing with bubbles! Today there is a bunch of white floating looking stuff and some yellow scum on walls. I figured it was time to use Nitros flush method which I am going to do tomorrow. By the way two weeks ago my TDS = 1000 PPM. My normal routine which I am not sure this is the way it is supposed to be or not has been to check PH and Bromine prior to every soak and TA 2-4 times a week. We have three kids so there are 3-5 of us that sit in the tub approx 5 days a week for 30-60 min each soak. I normally raise to TA to about 85, PH to 7.6, CH to 180 and try to keep bromine at 1-2ppm. We have a 550 Gal Caldera Cantabria tub with Ozinator and inline frog system. I have to add water every two weeks, usually a few inches of water in order to get back above the top sets of jets. Is this normal? We live in Oregon and temps right now are normally 40-50 degrees. During this two week period it is a steady decline for the TA and PH levels. By the time i have to add water which is every two weeks the TA = 60 and PH around 7.2 before water add and TA = 50 and PH = 6.9 after adding the 2" or so of water. So after adding water I add 3.1 oz of TA up or Baking soda which puts TA = 80-85 and PH = 7.6-7.7 and normally about 1.3oz of Calcium Chloride to get the CH level back up in the 180-190 range. I also normally add 1-2 TBS of MPS after each soak. Do this sound like a normal routine? It seems like I am constantly adding a lot of chemical which adds to the TDS. My TA & PH are always on a constant fall which is driving me crazy and the Bromine Levels always seem low which leads to another question, I started with a bromide bank of 30 ppm by adding Bromide Booster.....sodium bromide 99%. So every two weeks when I have to add water, do I need to be adding more sodium bromide to the bank? If so how much do I need to be adding? I really appreciate any advice. It seems like I am stuck in the same routine and am a rookie at this so I really could use some advise. I have learned a ton by reading this forum, but still have a lot to learn.

Thank you for any help!

[diggerdan4]

Fot got to mention above that I am on well water if this makes any difference. After Refill today, still having the same old trouble before adding anything to water I tested water I am sitting at TA = 50, PH = 7.6 and CH = 35. to start I added a little Metal and Scale approx 2oz. Then I added 1.2 oz Spa Down which dropped PH to 7.4 and dropped TA down to 30 So tried to get TA back up and added 3oz of baking soda which raised TA to 70 but raised PH up to 8 so now I am raising calcium up to about 110. which will put me at a CSI of .09 I was shooting for a PH of 7.6 TA of 100 and a CH of 110 for a CSI of .01. Would really love to get some advice from the experts here on what they would do with this. Seems like my TA wants to stay low which falls the entire time and brings PH down along with it.

Also like I mentioned above I have a fairly heavy bather load so have been topping off (approx 2") every two weeks, Do I need to be adding to my bromine bank each top off? If I decide to add Borax, would I have to add to this every top off also?

[chem geek]

MPS is net acidic so will lower the TA over time and with the lower TA the MPS will also end up lowering the pH more than carbon dioxide outgassing will increase it.

So if you want to continue to use MPS, then you'll need to add baking soda to maintain a TA level, probably closer to 80 ppm in order to have the pH be somewhat more stable.

2 ounces of Spa Down (dry acid aka sodium bisulfate) would lower the TA by about 11 ppm in 550 gallons so something in your measurement was wrong if you saw it go from 50 ppm to 30 ppm -- perhaps it was around 45 and you called it 50 and when it went down to 34 you called it 30. HOWEVER, with that amount of pH Down your pH should have gone much lower from 7.5 to 6.8 except that with carbon dioxide outgassing it might have been down to around 7.0 to 7.2 unless you were aerating the water. When you run the jets, that will have the pH rise with no change in TA.

If your water is getting cloudy and you don't have your bromine level ever get to zero, then you may need to use chlorine on occasion to shock perhaps once a week to keep the water clear. Also, your MPS will show up in your bromine test kit as bromine but MPS by itself is not a disinfectant. If you want to continue to use MPS with bromine, you'll need to either get separate MPS-specific test strips or get the Taylor K-2042 MPS interference remover, though that is for Taylor's 2000 series test kits such as the K-2106 used for bromine.

Bromide does not evaporate so you should not need to add more unless you have an ozonator. Ozone converts some bromine to bromate so depletes your bromide bank.

[diggerdan4]

Chem Geek, Thanks for your response!

So I checked everything tonight and here are the numbers I got using the Taylor K-2106:

PH = 7.9

TA = 55

CH = 95

Our tub does have an Ozonator so with out being able to test our bromide bank on water top offs (normally about 2 weeks) should I be adding to the bank? If so your best guess at how much? If not using MPS to shock brimide bank, what would be your product of choice?

Given the numbers above what process do I go through to get the TA up to 80 without raising the PH that is already too high?

We sat in the tub last night and since we have flushed, super chlorinated, refilled and balanced noticed that a bunch of the rotating jets seem to not be rotating very well. Not sure if this is from the way I have the tub balanced this time or what is going on there, but I think I will remove the sticky ones and soak them in vinegar.

[chem geek]

That's a good question for which I don't have a good answer. I'd say if your ozonator isn't producing bromine at a rate sufficient to maintain a decent level in between soaks, you can increase the bromide bank by no more than the standard 1/2 ounce per 100 gallons amount and see if that helps. If it does, then whenever such production drops low, you can raise your bromide bank accordingly. As you point out, without being able to test for the bromide level, you don't have an easy way of knowing what to do, but the production rate of bromine by the ozonator is a reasonable proxy to use.

If your pH tends to be too high, then don't raise the TA level. You can have 50 ppm and do all right though for supplemental pH stability you can use 50 ppm borates most easily added from boric acid. Usually though, when using the MPS that will not only lower the TA but keep the pH down as well so your higher usage probably has a lot of aeration of the water that tends to push up the pH from carbon dioxide outgassing.

Strange about the rotating jets -- those are plastic, correct? With your low TA and CH I doubt you've got calcium carbonate scale. If you soak the jets in vinegar and see fizzing from white scale, then that's calcium carbonate.

[diggerdan4]

So I have been keeping an eye on bromine level this past week after adding the bromide bank of 30ppm and it seems to stay around 1.5-2.5 ppm with just the bromine bank and the Ozonator, I turned the frog bromine cartridge totally off and after about 24hrs after soak, it climbs back up in the 1.5ppm range we are looking for. Since it is climbing back up in this range do I need to still be shocking with MPS or bleach once a week. It seems like when ever I do so it climbs up in the 10 ppm range, but dont want to quit shocking if needed for sanitary purposes. What about if the frog bromine cartridge is on does this shock in any way or is this just adding to the Bromide bank?

Also my PH has dropped a little now around 7.7 now so that is good, but am concerned about TA it seems to be down between 40-50ppm now testing with the Taylor K-2106 kit. Should I be concerned about this low TA? Should I do anything with the CH beings TA is so low it is around 100ppm