PH was WAY low, now WAY high

jlhaz

LifeTime Supporter
Aug 18, 2007
99
#1
Hello,

yesterday when doing my water testing, my PH measured at 6.8. I had a tablet holder in the water for a few days to make sure the water held chlorine because of the increase in teampertaures until I was able to get more bleach. I took the tablet holder out yesterday.

Last night I added about 75 OZ of Borax into the skimmer.

Today, my measurements show PH to be 8.2!

Could the tablets have made the PH go wacky? Should I add some acid to bring it down or wait a few days?

The chlorine level is holding steady at about 3-4

Thanks!
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#3
Borax raises PH. If your TA level is low enough that makes total sense.

Yes, you should add acid to bring it down, but this time use quite a bit less than you think you need.

We can give you a lot more help if you post a full set of water test results.
 

jlhaz

LifeTime Supporter
Aug 18, 2007
99
#4
Oh yes...sorry...I've just been using the everyday part of the kit because things have been going pretty well until this bump in the road :)

FC=1
CC=1
CYA=60
TA=200
PH=8.2
 

whoozer

LifeTime Supporter
Apr 2, 2008
633
Acton Maine
#5
You need acid to bring it down. Use the pool calculator to figure the correct amount :-D Just be careful as you don't want your cya to creap up too much too fast.
 

jlhaz

LifeTime Supporter
Aug 18, 2007
99
#6
whoozer said:
You need acid to bring it down. Use the pool calculator to figure the correct amount :-D Just be careful as you don't want your cya to creap up too much too fast.
I did use the pool calculator to try to bring up my PH. but my measurements must be off somewhere...maybe in my gallon measurements.

Whats strange though is that I always use the pool calculator to add bleach and it's always right on, so I just wonder if I messed something up someplace.
 

whoozer

LifeTime Supporter
Apr 2, 2008
633
Acton Maine
#7
Sorry jlhaz..it's late and my thoughts are garbled :roll: I didn't mean to imply adding ma would affect your cya just saw it was 60 and I know how easy it can go up. Anyway...

Based on 14k it says 25oz. of 31.45% of MA. I think I would only use 8-10 oz to start and retest. Maybe even less to be conservative. As it is easy to test ph.
 

Butterfly

TFP Expert
LifeTime Supporter
May 31, 2007
10,045
South Carolina
#8
jlhaz said:
Oh yes...sorry...I've just been using the everyday part of the kit because things have been going pretty well until this bump in the road :)

FC=1
CC=1
CYA=60
TA=200
PH=8.2
Hey J,

Try adding half the amount of acid, retest in an hour, and adjust as needed.

You know you gotta' shock that pool!

I'd work on getting that TA down!
 

jlhaz

LifeTime Supporter
Aug 18, 2007
99
#9
whoozer said:
Sorry jlhaz..it's late and my thoughts are garbled :roll: I didn't mean to imply adding ma would affect your cya just saw it was 60 and I know how easy it can go up. Anyway...

Based on 14k it says 25oz. of 31.45% of MA. I think I would only use 8-10 oz to start and retest. Maybe even less to be conservative. As it is easy to test ph.
No problem... :)

thanks for the info!
 

jlhaz

LifeTime Supporter
Aug 18, 2007
99
#10
jjparrish said:
jlhaz said:
Oh yes...sorry...I've just been using the everyday part of the kit because things have been going pretty well until this bump in the road :)

FC=1
CC=1
CYA=60
TA=200
PH=8.2
Hey J,

Try adding half the amount of acid, retest in an hour, and adjust as needed.

You know you gotta' shock that pool!

I'd work on getting that TA down!
Thanks for the info...

Do these #'s show that I have to shock? I thought if the chlorine held overnight at a pretty consistent level then i'm ok. My water is as clear as it has ever been.

I'll try to get to the store tomorrow for some MA
 

Butterfly

TFP Expert
LifeTime Supporter
May 31, 2007
10,045
South Carolina
#11
jlhaz said:
jjparrish said:
jlhaz said:
Oh yes...sorry...I've just been using the everyday part of the kit because things have been going pretty well until this bump in the road :)

FC=1
CC=1
CYA=60
TA=200
PH=8.2
Hey J,

Try adding half the amount of acid, retest in an hour, and adjust as needed.

You know you gotta' shock that pool!

I'd work on getting that TA down!
Thanks for the info...

Do these #'s show that I have to shock? Yes. 1 CC means you need to shock Also, FC dropping to 1 is too low. I thought if the chlorine held overnight at a pretty consistent level then i'm ok. My water is as clear as it has ever been.

It won't be for long if you don't shock!

I'll try to get to the store tomorrow for some MA
Here are a couple stickies to read:

"ABC's of Pool Water Chemistry" by duraleigh: http://www.troublefreepool.com/sticky.php?s=4953

"BBB" or, "What are all these pool chemicals?" by Waterbear: http://www.troublefreepool.com/sticky.php?s=94
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#13
You should shock because CC is above 0.5.

You have high TA, not low TA as I guessed previously. With high TA levels the PH will tend to drift up on it's own any time there is aeration of the water, which can happen from a SWG, waterfall, fountain, kids splashing, rain, etc. You will need to add acid regularly to keep the PH in a reasonable range. Try to keep PH between 7.2 and 7.8.

Experiment with the amount of acid you use till you find an amount that gives the desired result. Keep in mind that the amount of acid required will be lower when the TA is lower and that if you wait too long after adding acid before retesting the PH will have gone up from aeration and you won't be able to tell how much of the PH change was from the acid and how much was from high TA and aeration.

Longer term you should lower your TA, see this sticky for directions on lowering TA.
 

jlhaz

LifeTime Supporter
Aug 18, 2007
99
#14
JasonLion said:
You should shock because CC is above 0.5.

You have high TA, not low TA as I guessed previously. With high TA levels the PH will tend to drift up on it's own any time there is aeration of the water, which can happen from a SWG, waterfall, fountain, kids splashing, rain, etc. You will need to add acid regularly to keep the PH in a reasonable range. Try to keep PH between 7.2 and 7.8.

Experiment with the amount of acid you use till you find an amount that gives the desired result. Keep in mind that the amount of acid required will be lower when the TA is lower and that if you wait too long after adding acid before retesting the PH will have gone up from aeration and you won't be able to tell how much of the PH change was from the acid and how much was from high TA and aeration.

Longer term you should lower your TA, see this sticky for directions on lowering TA.
OK got it thanks...I'll use MA until this weekend when I'll have the time to dedicate to bringing the TA down using your method.

I do have an aerator on the pool so that should help with the process. Unfortunately my returns don't have eyeballs on them :(
 

chem geek

TFP Expert
LifeTime Supporter
Mar 28, 2007
12,082
San Rafael, CA USA
#15
jlhaz said:
yesterday when doing my water testing, my PH measured at 6.8. I had a tablet holder in the water for a few days to make sure the water held chlorine because of the increase in teampertaures until I was able to get more bleach. I took the tablet holder out yesterday.

Last night I added about 75 OZ of Borax into the skimmer.

Today, my measurements show PH to be 8.2!

Could the tablets have made the PH go wacky? Should I add some acid to bring it down or wait a few days?
With the measurement numbers you later posted (especially the TA of 200 ppm), adding only 75 ounces (about one box) of Borax to 14,000 gallons would only bring up the pH from 6.8 to 6.9. By any chance, when you measured the pH that was low at 6.8, did you take a water sample near the tablet holder? If the circulation was poor or the pump wasn't running, then the water around the tablet holder could have been quite a bit more acidic than that in the bulk pool water. Otherwise, I can't explain the dramatic difference. The high TA will lead to a rise in pH, but not by that much in one day.

Richard
 

jlhaz

LifeTime Supporter
Aug 18, 2007
99
#16
chem geek said:
jlhaz said:
yesterday when doing my water testing, my PH measured at 6.8. I had a tablet holder in the water for a few days to make sure the water held chlorine because of the increase in teampertaures until I was able to get more bleach. I took the tablet holder out yesterday.

Last night I added about 75 OZ of Borax into the skimmer.

Today, my measurements show PH to be 8.2!

Could the tablets have made the PH go wacky? Should I add some acid to bring it down or wait a few days?
With the measurement numbers you later posted (especially the TA of 200 ppm), adding only 75 ounces (about one box) of Borax to 14,000 gallons would only bring up the pH from 6.8 to 6.9. By any chance, when you measured the pH that was low at 6.8, did you take a water sample near the tablet holder? If the circulation was poor or the pump wasn't running, then the water around the tablet holder could have been quite a bit more acidic than that in the bulk pool water. Otherwise, I can't explain the dramatic difference. The high TA will lead to a rise in pH, but not by that much in one day.

Richard
You know, I really don't remember if it was near the tablet holder or not...it could have been..I really don't remember though.

So my plan is to buy some MA, lower the PH thaty way and then follow the TA sticky this weekend to bring the TA down.

Oh yeah, 1 more thing...can I shock while doing all of this? or should I do them one at a time?

Thanks!
 

Rangeball

Well-known member
May 25, 2007
785
#18
jlhaz, you mentioned earlier that you are using the "every day" part of the test kit. By any chance are you using the OTO test for chlorine and reporting the 1ppm as both FC and CC? OTO only tests for total chlorine.

If this is the case run an FAS/DPD test to see if you truly have CC. No reason to shock if you don't need to, especially when you're trying to regulate PH like Richard mentioned.

Also, if your CYA is 60, you need to maintain a lot higher FC than 1 ppm. Just checked, target FC for 60ppm CYA is 6.8. Have you seen the Chlorine/CYA chart in the sticky section of the chemistry 101 forum?
 

jlhaz

LifeTime Supporter
Aug 18, 2007
99
#19
Rangeball said:
jlhaz, you mentioned earlier that you are using the "every day" part of the test kit. By any chance are you using the OTO test for chlorine and reporting the 1ppm as both FC and CC? OTO only tests for total chlorine.

If this is the case run an FAS/DPD test to see if you truly have CC. No reason to shock if you don't need to, especially when you're trying to regulate PH like Richard mentioned.

Also, if your CYA is 60, you need to maintain a lot higher FC than 1 ppm. Just checked, target FC for 60ppm CYA is 6.8. Have you seen the Chlorine/CYA chart in the sticky section of the chemistry 101 forum?
No, when I was asked for a full set of #'s I pulled out the rest of the kit and performed those tests. I saw the Chlorine/CYA sticky but didn't think I needed it because I was just using the Pool Calculator.

So I should probably use the Chlorine/CYA chart to find out my desired chlorine level, then plug the numbers into the pool calculator to calculate the amount of bleach, etc I need?