Trouble bringing high Alkalinity down, initial set up

[Lee In VT]

Hi. I just bought a 250gal hot tub and filled it with my hard but very good well water. Using 'Instatest strips' the alkalinity is in the 180+ range. As directed I've been adding pH decreaser (sodium bisulfate, " Proteam Spa pH Decreaser") by the tablespoon dissolved in water for two days now, probably over 10 tablespoons, and the Alkalinity won't fall into the desired 80-120. The pH is also on the high side (between 7.8 - 8.4) despite all the chemical although initially seemed to fall but now seems higher. Total hardness tested in the 250-450 range. I finally called the dealer who said it can take up to 5 days to lower the alkalinity and I should stop adding chemical and wait for it to chelate the minerals. I've reviewed TFP but couldn't find this specific question previously posted.

Any advice? Should I use something stronger to lower the Alkalinity? Should I continue to add more pH decreaser now? (I was told to first get the alkalinity into the good range then adjust pH as needed). I am planning to use Pristine Blue for sanitization and the tub has an ozonator.
Thanks in advance, very frustrated.
Lee

 

[woodyp]

Who is testing and HOW are they testing your PH? I just used poolmath located here in pool school and it says it would only take one ounce of muriatic acid to lower your PH from 8.2 to 7.4., which will in turn help lower your total alkalinty It will probably take 3 or 4 cycles of "tubbing" during which the jets should raise your PH again. Then you just repeat the cycle of lowering the Ph and your TA should gradually be falling. Could your PH be a LOT higher than that? I don't think so.
Welcome to TFP.

 

[Lee In VT]

I'm doing the testing myself using instant read test strips from the dealer. I have experience with pH test strips previously so I think I know how to read these strips. The pH reducer they gave me to use is sodium bisulfate but as I said multiple applications haven't budged the level of alkaline. The dealer said give it a few days to work. I guess I'll try the muriatic acid if there's no change. Thanks for the advice. I wonder if anyone has experience using sodium bisulfate?

 

[jblizzle]

Test strips can be notoriously inaccurate. You would be better getting a cheap drop based pH test from Taylor.

 

[Lee In VT]

Thanks, I agree and will order a test kit. It would be good to have a quantitative measure of the water's solutes rather than these qualitative colorimetric strips. I would take a water sample in to the dealer for testing but it's over an hour's drive away. Meanwhile I'd like to try the one ounce of muriatic acid you suggested and stop wasting my time with the sodium bisulfate pH reducer.
Lee

 

[jblizzle]

Well getting a kit is the best method. We generally do not trust pool store testing either.

 

[TUBLOVE]

Hi Lee,

Your dealer said "5 days to lower TA"? No! That's just crazy. We learned the very hard way that taking the advice of our dealer made for some jacked-up tub levels and biofilm. So we did a million hours of research and learned from the experts online. After alot of trial and error, we are now able to fresh fill and be perfectly balanced in about 12 hours. We use Bromine system.

We have a 400+ gallon tub (1 year old) and also use well water. A fresh fill presents TA levels at 240 every time. It takes a total of 26 oz. of muratic acid to bring our TA levels to 80-100 [where we like it and the tub is happy]. Initially I put 20 oz in and let the jets do their thing for several hours. Then I gradually add the last 6 oz. to get to the 80. Something like 3 oz, test, 2 oz, test. etc.

We couldn't get balanced without a Taylor test kit. Anyway, once that TA is good, we tweak the PH, then the BR lastly.

On a side note: we use muratic acid on the fresh fill, but any tweaking to the TA between fills and we use dry acid. Rarely do we ever have to tweak though and we tub about 6x a week. We are so happy with our chemical process and are addicted to the fresh, clear sparkling water we have come to love. It took alot of work to learn the basics and trust the process. There are many posted articles on a couple different forums that are invaluable.

Good luck, Lee!
Kelley

 

[Lee In VT]

Thanks. I put in 1/2 oz of muriatic acid and both TA and pH fell to the normal range. Guess I can now proceed with the sanitation steps. They gave me Pristine Blue system to use so I'll try that. I was never a fan of chlorine.

 

[jblizzle]

Oh my ... I have to caution against the Pristine Blue. That is just a bunch of copper that can result in stains in the pool and green hair.

Please search the forum about it and other alternative sanitizers. There are very few methods that are approved for use in pools / spas and PB is not one of them.

 

[Lee In VT]

Unfortunately I've already added the Pristine blue chemicals as directed, before reading your post. Now that it's in what would you recommend? Luckily I'm bald, but my wife isn't. What is your favorite sanitizing system for small spas? I'd hate to have to drain the hot tub and start over, but I can.

 

[jblizzle]

Ran across this while doing some research:
giving-pristineblue-a-try-t8959.html

And this is a good one too:
alternative-sanitizers-and-chemical-free-pools-the-truth-t3025.html

The only way to get the copper out now is draining and refilling. I do not have a spa, so I have no favorite. These are the options:
1. Chlorine (manual additions or salt water chlorine generator)
2. Bromine (has a different smell that many do not like)
3. Baquacil/biguanide/PHMB (do not even think about it )
4. Nature 2 with MPS

The SWG and Nature 2 required hardware that you do not currently have and Baq is just no good. That leaves manually adding chlorine or bromine. There are stickies in this sub-forum that discuss both.

They all have + and - and the best option depends on how your tub is used.

If you did not use too much of the PB, you could just leave it in and do not add any more and then start with chlorine / bromine.

 

[Lee In VT]

Thanks for the advice. I reviewed the interesting links you offered. The Pristine blue system does use three other agents, one to stabilize the copper, the other to clarify. The third is a chlorine based shock, to be applied after each use. (and my hot tub has an ozonator too, FWIW) They even mentioned about the risk of green hair and staining of certain pool surfaces if levels get too high. Guess I'll leave it in and convert to chlorine as it diminishes. I don't really care about mild tub staining and I'll warn my wife to wear a bathing cap. I'm bald but a green pate might look good on me.

 

[jblizzle]

So they are using chlorine which is required to be safe, but you will quickly find that those "specialty" products cost WAY more than what you can find in grocery stores.

 

[Lee In VT]

I hear you Jason. They gave me the full kit (and kaboodle) for 'free' when I bought the spa. A $200 value they claimed.

 

[Lee In VT]

I should correct my statement about the Pristine Blue system relying on chlorine (sodium dichloro.....) to shock the system. Actually they use that as a backup 'extra' for heavy use, whatever that is. Their main compound for shocking the spa is potassium peroxymonosulfate ('PristinePower') both for initial and ongoing use. Sounds like a peroxide like solution, releasing oxygen to sanitize?

Kelly, I'm amazed at how much muriatic acid you have to use. Our well water comes out of limestone here, hence the high alkalinity. Only 1/2 ounce of acid brought our 250 gallons to neutral, though I must say both pH and TA are back up after just a single use. Somehow it just didn't feel right adding concentrated hydrochloric acid to my little hot tub, but I'm getting used to it.

 

[chem geek]

Their main compound for shocking the spa is potassium peroxymonosulfate ('PristinePower') both for initial and ongoing use. Sounds like a peroxide like solution, releasing oxygen to sanitize?

No, that is not hydrogen peroxide. Peroxymonosulfate aka monopersulfate (MPS) is a sulfate with an extra oxygen (HSO₅^-). So it has the "extra oxygen" just as ozone has one more oxygen atom than oxygen gas and how hydrogen peroxide has one more oxygen than water, but these are all different compounds where ozone is the strongest, then hydrogen peroxide, and then MPS, at least for the levels used in spas.

MPS is not a disinfectant unless it is used in conjunction with silver ions at hot spa temperatures. Only Nature² has been approved by the EPA for use a disinfectant with MPS since Nature² provides the silver ions and they went through the thorough testing required to pass EPA DIS/TSS-12. Pristine Blue is copper ions only, not silver ions, and copper ions do not have the same effect with MPS. In fact, as shown in this post, copper ions do not kill fecal bacteria.

You will note that the PristineBlue website no longer says that they kill bacteria and any reference to a bactericide has an asterisk to text that says "*Nonpublic Health Bacteria" which is a reference to the fact that it does not kill fecal bacteria.

 

[Lee In VT]

Yes, I did notice the phrase "Nonpublic Health Bacteria" and wondered about that. I guess I'll stick with the chlorine product for shocking the water after use. It might be that copper inhibits the proliferation of the bacteria rather than killing them. I know of copper based paints being used as antifouling paint on boat bottoms.