pH dropping

[Toad_stools]

Hey guys. pH has been very steady at 7.4 since we opened the pool a few weeks ago. I noticed a marked drop over the past couple of days and it’s now about 6.8. I put about 1kg of baking soda in yesterday and this AM. Should this do the trick to bring it back up? I see here and other places online others will use ash as well, but is this the exact same thing? Or is it more effective? Also, what causes a drop like that so quickly? Not much has changed over the last week except that the weather has gotten warmer and we’ve been using the pool more. Thanks.

edit to also say that there is also now a lot of pollen and tree buds falling into the pool over the past two days.

 

[ajw22]

pH only drops when you add acid, Naturally your pH will rise.

What chemicals are you adding to your pool?

What is your TA?

Effects on pH and TA are:

• Baking Soda = big TA change, small pH change
• Borax = big pH change, small TA change
• Soda Ash/Washing Soda = big pH change, big TA change.

Best way to raise pH is simple aeration which does not affect the TA.

PH - Further Reading

www.troublefreepool.com

Aeration - Further Reading

www.troublefreepool.com

 

[Toad_stools]

pH only drops when you add acid, Naturally your pH will rise.

What chemicals are you adding to your pool?

What is your TA?

Effects on pH and TA are:

• Baking Soda = big TA change, small pH change
• Borax = big pH change, small TA change
• Soda Ash/Washing Soda = big pH change, big TA change.

Best way to raise pH is simple aeration which does not affect the TA.

PH - Further Reading

www.troublefreepool.com

Aeration - Further Reading

www.troublefreepool.com

Ok. Well I have been adding CYA over the past week to get it up. It’s been really low (near 20), so have been adding About 300g or so each day into a sock in the skimmer. I’ve probably added about 1kg of stabilizer over the past week. But that’s been it. Would that lower the pH?

edit. TA is about 110.

 

[Toad_stools]

pH only drops when you add acid, Naturally your pH will rise.

What chemicals are you adding to your pool?

What is your TA?

Effects on pH and TA are:

• Baking Soda = big TA change, small pH change
• Borax = big pH change, small TA change
• Soda Ash/Washing Soda = big pH change, big TA change.

Best way to raise pH is simple aeration which does not affect the TA.

PH - Further Reading

www.troublefreepool.com

Aeration - Further Reading

www.troublefreepool.com

Thanks so based on above maybe I shouldn’t added some borax since my TA seems ok? I’ll see what happens over the next 24 hours after adding the baking soda, but I didn’t realize it has such a big effect on TA.

 

[IceShadow]

Yeah, aeration would have been best with a TA of 110. What are you chlorinating with?

 

[Toad_stools]

Yeah, aeration would have been best with a TA of 110. What are you chlorinating with?

Salt water generator

 

[IceShadow]

Ok, so no pucks or granular shock. I would have to assume the CYA lowered the pH. What is your pH and TA now that you’ve added the baking soda?

 

[ajw22]

CYA is a mild acid and lowers your pH some. That is what did it.

 

[Toad_stools]

Ok I just tested it and it’s already back to about 7.5

Ok, so no pucks or granular shock. I would have to assume the CYA lowered the pH. What is your pH and TA now that you’ve added the baking soda?

I just tested and it’s now back to 7.5. That was fast. Thought it would take a lot longer to show results.

 

[Toad_stools]

Thanks for the quick assistance guys. I feel like I’m on a long journey here learning about all this stuff. I just don’t want to screw something up!

 

[IceShadow]

If the pH drops again from additions and your TA is above 80-90, aerate and it will come up again.

 

[Toad_stools]

If the pH drops again from additions and your TA is above 80-90, aerate and it will come up again.

Thanks. Yea I noticed that after I also had the kreepy krauler in and the kids went swimming it came up. So that’s good to know.

 

[ajw22]

Even with TA of 60 or above aerate first and see how your pH responds if it is low.