pH not rising with aeration

[P00LNerd]

I added some dry stabilizer to increase my CYA, and it dropped my pH from an already low 7.2 down to 7.0. I figured no problem, a day or three of aeration and I’ll have it right up into the mid-7’s, I’ve done it many times before, but this time progress appears to be much slower than I remember.

It has been 36 hours, and pH has only increased from 7.0 to 7.1, whereas memory tells me I should be seeing more like 0.3 ppm in 36 hours.

Aeration is done by a sprinkler head on one return, and simply aiming the other return up at the surface. I have the solar cover folded back in both areas, to expose the surface, but otherwise covering the rest of the pool, as we’re still seeing high 40F’s overnight (today was 47F low to 81F high).



I suspect my pump is running slower (for off-season) than other times I’ve used this trick, and having the cover over most of the surface is probably another factor, but which is likely the bigger detriment to raising pH?

 

[Mdragger88]

I would say the cover.
Aeration also takes time

 

[PoolStored]

cover over most of the surface is probably another factor

Big one.

 

[ajw22]

The cover prevents CO2 outgassing which prevents pH rise.

Aeration - Further Reading

www.troublefreepool.com

What Causes Aeration to Raise pH​

Anything that increases the surface area of the air-water interface increases the rate of carbon dioxide leaving the pool water. The outgassing of CO2 causes pH to rise.

Pools are intentionally over-carbonated both to provide a pH buffer and to saturate the water with the carbonate portion of calcium carbonate to protect plaster surfaces from dissolving. In other words, there is a lot more dissolved carbon dioxide in the water than would naturally occur in equilibrium with the air (though not as much as a carbonated beverage!).

As for why the pH rises, the easiest way to explain it is that some of the carbon dioxide in water is carbonic acid -- that is, carbon dioxide plus water makes carbonic acid -- so removing carbon dioxide is like removing carbonic acid. Removing an acid from the water makes the pH rise.[

 

[P00LNerd]

Thanks, guys! Cover will come off tomorrow, then. It'll be cloudy and raining the next 6 days anyway, so little to be gained from having the solar cover on.

Pool water is holding 69 - 73 F with cover on sunny days, which is great considering we were 59F - 61F water temperature a week ago. Daughter even went for a swim today, when we hit 81F air temperature mid-afternoon. But we won't be seeing much higher than 60F air temperature the next several days, no one will be swimming.

 

[Mdragger88]

Btw - with your ta above 100 the ph will rise anyway. No need to rush it. If you wanna leave the cover on to keep it comfortable for swimmers that’s fine too. Your ph is fine where it is.
It can be hard not to tinker but either way I wouldn’t sweat it too much.

 

[P00LNerd]

Well, yeah... I know 7.1 ain't bad. But that big red exclamation mark staring at me from the PoolMath Overview page just won't leave me alone, so I must drive it toward middle of range. Human nature.

I didn't have a chance to get a baseline this morning, but suspect it was still holding 7.1, as it has been the last few days. I pulled the cover off, and now just 3 hours later, it's already jumped to 7.3. A little rain pelting the surface probably helped with the aeration, as well.

I'm bummed that adding stabilizer didn't even nudge my TA a little, I think it's just destined to be forever high. I'm not sure how much that really matters, but again, those Darn red exclamation marks shout at me from the PoolMath overview page.

Psychologists could learn a lot from studying human reaction to PoolMath. Or conversely, the developers of PoolMath might want to reconsider where they throw those alarming red exclamation marks, since I keep hearing "it doesn't matter".

 

[ajw22]

Well, yeah... I know 7.1 ain't bad. But that big red exclamation mark staring at me from the PoolMath Overview page just won't leave me alone, so I must drive it toward middle of range. Human nature.

Are you going to let your life be driven by robots?

You have free will.

I'm bummed that adding stabilizer didn't even nudge my TA a little, I think it's just destined to be forever high.

Stabilizer does not lower TA. Adding Muriatic acid does.

I'm not sure how much that really matters, but again, those Darn red exclamation marks shout at me from the PoolMath overview page.

Psychologists could learn a lot from studying human reaction to PoolMath. Or conversely, the developers of PoolMath might want to reconsider where they throw those alarming red exclamation marks, since I keep hearing "it doesn't matter".

The exclamation marks get your attention, get you thinking, and focused on certain areas of concern.

You have the judgement to determine the correct action, not PoolMath.

 

[P00LNerd]

Are you going to let your life be driven by robots? ...You have the judgement to determine the correct action, not PoolMath.

You are apparently not familiar with my particular flavor of OCD.

 

[Newdude]

Go into settings, then advanced settings and turn off 'ideal level'. Poolmath doesnt know understand the date, the climate, the fill water, the weather, or what you've found works best with your unique pool.

Any 7.X Ph is equally fine.