Closed pool pH rise

[ssgtob1]

Hi all,
My pool is currently closed. I had an issue last winter with too high of pH causing scaling. I've been checking the pH and adding acid every other week or so. Every time I check it, it has risen to 8.2. The TA was fine when I closed it and has been at the same level, 70, every time I check it. What would cause this rise?



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home
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Build Type: Plaster
Volume: 16000 gallons
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Latest Test Result Summary:
FC: 3.5
CC: 0.0
pH: 8.2
TA: 70
CH: 300
CYA: 40
SALT: 3200
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[YippeeSkippy]

When was the pool built? New pools with new plaster have this issue as the plaster cures.

You say you've been adding MA while closed?- how are you mixing that in??

Maddie

 

[ssgtob1]

When was the pool built? New pools with new plaster have this issue as the plaster cures.

You say you've been adding MA while closed?- how are you mixing that in??

Maddie

It's three years old. I pour it in a corner and then agitate it with one of the pool brushes, a lot.

 

[Texas Splash]

"SS", we expect pH to naturally rise in colder water, but that cold water temp also helps to balance that effect. What's your water temp? I"m guessing still chilly. Heat pump not in use. So even if I use 50 degrees as a conservative estimate, your CSI is only at about 0.05 which is well-balanced and scale should not be an issue with those test numbers.

 

[cfherrman]

How low are you dropping your pH?

 

[wireform]

I can't imagine the water to be over the 40° mark.

 

[ssgtob1]

I can't imagine the water to be over the 40° mark.

It's definitely around 40.

 

[ssgtob1]

How low are you dropping your pH?

7.5

 

[Texas Splash]

It's definitely around 40.

Then you should definitely be good. Your CSI should be slightly negative, even if the pH is at 8.2. I'd let it settle in the 7.8-8.2 range and leave it alone until the water temps begin to increase.