Zero Alkalinity with pH greater than 8.6. Help!

[Lreit]

We are first time pool owners working to get our pool back on track after the winter. Even after adding 25 lbs of Baking Soda on Wednesday, we still have a TA of 0 with a pH of >8.6. Have added 32 oz of MYA on Wednesday and Thursday nights with seemingly no impact on lowering the pH.

TC = 2
FC = 1.4
CYA = 55
pH = >8.6
TA = 0
Total Hardness = 278
Salt level = 1800

Has anyone ever heard of this problem? Any thoughts or suggestions on what to do?

 

[Patrick_B]

Welcome to TFP!

I'm sorry to be blunt, but what you are describing simply isn't possible. What are you using for testing?

You cannot have TA 0 and high pH. That TA would be pH <4.5

 

[Lreit]

That's the whole issue. We've used the home testing kit confirming the very high pH but the water never changed on the alkalinity test from green to red, even after 100 drops. We've also had an computerized BioGuard test done 3 times on different days all of which showing 0 TA and a high pH. They were stumped as well.

 

[Donldson]

the water never changed on the alkalinity test from green to red, even after 100 drops.

Your problem isn't 0 TA, it is a misinterpretation of the test. 0 TA means the test turns red immediately without adding any drops. What you are describing is an incredibly high TA, which makes a lot more sense.

EDIT: Oh, and pool store computer testing is worthless and this backs that up quite well. Your TA is more likely off the charts high and creating an error that it is reporting as zero.

Ah, and welcome to TFP!

 

[Lreit]

Ok, so if that's the case, which does make much more sense, why is there no change in pH despite adding a total of 4 pints (2 pints/night) of muriatic acid? What would you suggest to bring down the pH?

Thanks!!

 

[AimeeH]

If you are testing PH with the basic Taylor 1000 drop test, the max reading for PH is 8.2. If that is what you are reading it could be much higher.

 

[Donldson]

Continuing to add MA is all you can do, and if your TA reading is accurate it is going to be a long process. Use PoolMath to figure out how much MA you need to drop from 8.6 to 7.2, which will be gallons by the look of it. From there it will just be a process of keeping your pH down in the lower 7's and burning off the TA.

 

[zea3]

With a very high pH reading it could take several additions of acid to get the pH low enough to register a change on the test. Try using PoolMath to lower the pH to 6.8
Be sure to enter all your test results as that may affect how much acid you need to lower pH. Add the recommended amount of acid and let the pump run about 1/2 hour before testing again. Check that you are entering the correct strength of acid in Poolmath. Continue to lower the pH until you are able to see a change on the test results. Be sure the pump is running on low speed and the returns are pointed down so the surface of the water stays as smooth as possible. You don't want the water to churn at the surface since the aeration will raise your pH. Also turn off any fountains or water features that churn the surface of the water. Let us know how this turns out.

 

[Lreit]

Ok, thanks! Is there a maximum amount of acid you can add at one time?

We will keep you updated. Thanks again for the help!

 

[AimeeH]

I'd follow pool math and keep attempting to go from 8.6 down to reasonable (7.2 or maybe lower if you want)and wait and test again and add again as mentioned above since you truly don't know how high it is. The test stops at a certain point. So you don't know if you're WAY high or just a bit over where the test stops reading.

 

[JamesW]

If your reagents are good, then the test will eventually go from green to red. Add as many drops as needed to make the change. If it doesn't change, the test might be bad.

What was the last good TA test that you had and what was added since then?

What test kit do you have?

 

[AimeeH]

My post was referring to the PH test and not TA. At any given point after adding acid if it still reads the highest on your test kit, you don't know how far above that highest reading you actually are.

Edit

So I think your focus should first be on lowering your PH to a level where you can get a reading since both PH and TA seem to be off the charts. Lower PH to a readable level then we can deal with TA.

 

[Patrick_B]

Ok, so if that's the case, which does make much more sense, why is there no change in pH despite adding a total of 4 pints (2 pints/night) of muriatic acid? What would you suggest to bring down the pH?
Thanks!!

Maybe a rhetorical answer by now, but it's simply because the pH and TA are so high that 4 pints makes only a tiny reduction to the pH.

Ok, thanks! Is there a maximum amount of acid you can add at one time?

We will keep you updated. Thanks again for the help!

Sure!

There is, and that maximum would be whatever the volume is as indicated by the Pool Math calculator to reduce your pH a given amount. Say, for example from 8.6 down to 7.2 the calculator says 80 ounces then that would be your maximum. That is just an example, so don't use that number and verify what you need with the calculator.

Keep in mind, that with your situation the pH is going to rise back up very quickly. You'll have to keep at this for a while checking pH and adding acid daily until the pH rise slows down. By the time it does, your need for testing and acid addition frequency will decrease. You'll have a much better feel for it by this time, and see what I mean.