What's wrong with my PH reading?

[jkrupp]

Hi, our pool is only about 6 weeks old. For the first month we had a free service and they balanced the water. I tested it myself and the PH was 7.6

The pool has been drying our skin out like crazy so I decided to test everything again. TA is 90, CYA is between 30 and 40, Ch is 230, and Fc was 5.

PH however, was a bright hot pink that was not on the Taylor color spectrum at all. Thought it was user error and tried again, same result. I opened the Oreq test kit the builder gave us and used that, and same reading. Off the charts bright pink. Does this mean my PH is way high? How could this have happened if the water was previously balanced? Our tap water is 7.8 so even if it hadn't been balanced it shouldn't be that high...

Any idea what is happening?

 

[PoolingAround]

New pool means new plaster which means higher PH. Usually stabilizes after a year. Also, aeration causing ph rise. Any fountains/spillover, etc?

 

[jkrupp]

Thanks poolingaround, no we do not have any fountains or extras at all, just the basics. Should I do nothing then, and not worry about it for now? Could a high PH cause skin irritation?

 

[pooldv]

Yes, high pH irritates skin, eyes and causes scale build up in the pool. It is important to keep PH 7.6 to 7.8 at all times. More here, Pool School - Calcium Scaling

 

[jkrupp]

pooldv, do you know of any reasons the pH can rise from 7.6 to this high, with no aeration in the last couple of weeks? If indeed is is because of new plaster, I'm not sure how to combat this.

 

[Richard320]

You show having the Taylor K-2005 test kit. Use the acid demand test and bring that sample down to 7.4 or thereabouts. That should a) prove to you that you're not crazy, that it really was off the scale and b) help you calculate how much acid to add.

 

[pooldv]

pooldv, do you know of any reasons the pH can rise from 7.6 to this high, with no aeration in the last couple of weeks? If indeed is is because of new plaster, I'm not sure how to combat this.

It is completely normal. PH needs to be tested several times per week, especially at first.

 

[jkrupp]

Well that is a bummer, so I will need to continue to lower the pH, probably weekly, for the next year or so?

Thanks, I appreciate the help!

Thanks richard, I will do that right now

 

[pooldv]

Yes, it is definitely part of the deal. As you add acid to lower PH it will also slowly lower TA. Lower TA (60-70) will help to slow the pH rise. And as the plaster cures the upward pressure on pH will slow.

 

[jkrupp]

Thanks pooldv! And one more question.. I'm sure this information is on the site but I couldn't find it.. my acid demand test required 3 drops to get to 7.4. The test kit says to refer to the treatment table which I don't seem to have. Does the number of drops correlate to how much muriatic acid to add?

 

[PoolingAround]

This is what I used initially to figure out what to add. Now I just go by feel. Like a boss. LOL

https://www.troublefreepool.com/calc.html

 

[jkrupp]

Ah how did I forget pool math? I just used it last week for my hot tub refill. Thanks PoolingAround! Hopefully I can be a boss soon too.

 

[Richard320]

Thanks pooldv! And one more question.. I'm sure this information is on the site but I couldn't find it.. my acid demand test required 3 drops to get to 7.4. The test kit says to refer to the treatment table which I don't seem to have. Does the number of drops correlate to how much muriatic acid to add?

3 drops is 1.5 pints of acid in 10000 gallons. So for 13000 gallons, 1.3 * 1,5 = 1.95 pt. Call it a quart.

When the pH is not at the max, poolmath is a whole lot easier. But you could be at the top or waaaaay over the top and it will all read the same.

 

[jkrupp]

Thanks Richard!! So helpful. Just about to head to Home Depot.

 

[Richard320]

Thanks Richard!! So helpful. Just about to head to Home Depot.

Check the strength on the jug. A lot of times they sell "green" or "low-fuming" acid that is diluted, yet full price. Full strength is 31.45%.

 

[jkrupp]

Check the strength on the jug. A lot of times they sell "green" or "low-fuming" acid that is diluted, yet full price. Full strength is 31.45%.

Oookay... I saw the 31.45% and also one that was 14% at HD. I bought the 31.45% and hoped I had gotten the right one!