Low PH

[shedlock22]

Hello all,

I had a bad winter, tons of leaves and algae to greet me (cheap cover which has since been tossed), so I added 6 lbs of shock to clear things up. Lots of vacumming, etc and here is where I'm at today with a Taylor test kit.

TA - 130
CH - 210
FC - 7.8
CC - maybe .5? There is a hint of red at .4 and it's clear at .6
CYA > 100 as the black dot cannot be seen before the gauge starts.
My PH reading is yellow so it's below 7 after adding one bag of soda ash.

My pool is an 18' round, 48" deep, salt, and is covered when not in use.

Looking for advice on how to raise PH, after adding 4# already the PH didn't move.

 

[mknauss]

With a TA of 130, your pH cannot be below 6, or at least not for long.

Check your testing. Be sure you TA is at that level.

With that level of CYA, may as well drain off half the volume and plan to do it a second time before messing with things.

 

[HermanTX]

It may be best to address the CYA first as you have to drain at least half your pool. So your other chemistry levels will all change.
Also please read Recommended Pool Chemicals

 

[shedlock22]

ugh man that sucks but I think that's probably the best route. Could the CYA be that high from the shock? I added one bag of stabilizer as soon as I got the water clear.

 

[mknauss]

What is 'shock'? Did you test the water before adding anything?

 

[shedlock22]

What is 'shock'? Did you test the water before adding anything?

this is what I added

https://www.lowes.com/pd/Clorox-Pool-Spa-Shock-XtraBlue2-6-pk/1003085510

I did not test prior to adding, it was very green

 

[mknauss]

How much. Do not use that stuff very often. Adds copper.

 

[shedlock22]

6#

 

[mknauss]

6#

That added 52 ppm FC and 48 ppm CYA.

 

[tikoh]

That added 52 ppm FC and 48 ppm CYA.

A little less, clorox is funny because they mix more stuff in there and have less dichlor...

@shedlock22 dichlor shock (and trichlor pucks) also lower your pH. The amount you added would have dropped your pH by as much as 1.5.

It's best to switch to liquid chlorine (bleach).

 

[shedlock22]

After draining off half the water and refilling, new readings are:

TA 170
CH 210
FC 5.4
CC .2
CYA 42

The PH reading is still yellow.

 

[mknauss]

Be sure you are testing the TA properly.
What test kit are you using?

 

[shedlock22]

A little less, clorox is funny because they mix more stuff in there and have less dichlor...

@shedlock22 dichlor shock (and trichlor pucks) also lower your pH. The amount you added would have dropped your pH by as much as 1.5.

It's best to switch to liquid chlorine (bleach).

yes, am planning on doing so when I need to, I think I'm right in the recommended range at the moment.

 

[shedlock22]

Be sure you are testing the TA properly.
What test kit are you using?

Taylor K-2006

 

[mknauss]

Then you cannot have a TA of 170 and a pH under 7. Check your testing protocol.

 

[shedlock22]

would you expect TA to be higher?

 

[mknauss]

would you expect TA to be higher?

No. Depending on how low the pH is, the TA would be close to 0

 

[shedlock22]

ok, I will recheck them both. I am pretty sure I'm testing both properly as I have watched the Taylor videos on youtube several times.

 

[mknauss]

Show us a picture of your pH test.

 

[JamesW]

My pool is an 18' round, 48" deep, salt, and is covered when not in use.

Leave it uncovered for 24 hours to allow any carbon dioxide to get out.

Brush the pool a few times.

Maybe get some new reagents to be sure.