I have high TA fill water and I usually just let my TA come down over time but this year I'm going to aerate to lower it. My TA is 110 ppm and with my aerator setup it took me 6 hours to go from 7.2 to 7.4. Not hardly what I was expecting. Im in the process of improving my aerator. I have a 2 speed pump and turning it on high will probably put a ton more bubbles but I don't want to run my pump on high. High is 2HP and low is 0.25HP. Anyways I was just wandering about everyone elses setup and how fast it raises the pH.
Aeration Time For Lowering TA
- Thread starter smackdab
- Start date
I just leave my pump running with my eyeball pointed up. I also have a SWG. It talkes a few days for PH to rise back up unless you can run pump 24/7
Day(s) not hours for raising pH during a lowering TA process. It's not meant or possible to do this in hours of time measures. It's a process that takes time.
Actually, pH rising .2 in a 6 hour period is fairly quick rise. Aerating to raise pH is not something that happends quickly at all. It could likely take several days to raise it for example from 7.2 - 7.8. How quickly this happens depends a lot on the TA.
If you dont mind me asking.... are you lowereing TA just to meet a number or are you lowering it so that your pH does rise so quickly? quick pH rise is the only reason to actively lower the TA.
If you dont mind me asking.... are you lowereing TA just to meet a number or are you lowering it so that your pH does rise so quickly? quick pH rise is the only reason to actively lower the TA.
Every year my pH holds steady around 80 ppm TA. I don't guess I'm in a hurry to get it down there, I just figured that was kind of slow. I was figuring I could raise it from 7.2 to 7.8 in 6 hours. 
I think I can actually do better than 0.2 but just have to see when 6 hours is up to see.
I think I can actually do better than 0.2 but just have to see when 6 hours is up to see.
My improvement didn't help any. Still 0.2 rise in 6hours. I have a venturi setup on the return fitting. I went from one line sucking air to 3 lines sucking air with no change. I guess one line is already maxed out. I guess Days not Hours it is.
I started working mine down two months ago. About 160 down to 60 and I just got there. I push the pH down to 7.2 every single time too.
Would it take the same 6 hours to go from 7.4 to 7.6 as it does from 7.2 to 7.4?
I know you have to add more acid at lower pH to lower it 0.2 therefore removing more TA. Pool school recommends going all the way up to 7.6. If it takes 6 more hours to go from 7.4 to 7.6 then that is a little less efficient than adding acid going from 7.2 to 7.4 every time. Maybe this will explain what I mean.
16000 gallons of water and using 31.45% MA
7.6 to 7.4 = 13 oz MA = -3.2 TA
7.4 to 7.2 = 19 oz MA = -4.6 TA
As you can see I'm gaining better ground going from 7.4 to 7.2 every time and actually would gain better ground going from 7.2 to 7.0 but I don't know if I want my pH hovering that low. My math says I'm down to TA 96.2 ppm at this point although I haven't tested to confirm.
I know you have to add more acid at lower pH to lower it 0.2 therefore removing more TA. Pool school recommends going all the way up to 7.6. If it takes 6 more hours to go from 7.4 to 7.6 then that is a little less efficient than adding acid going from 7.2 to 7.4 every time. Maybe this will explain what I mean.
16000 gallons of water and using 31.45% MA
7.6 to 7.4 = 13 oz MA = -3.2 TA
7.4 to 7.2 = 19 oz MA = -4.6 TA
As you can see I'm gaining better ground going from 7.4 to 7.2 every time and actually would gain better ground going from 7.2 to 7.0 but I don't know if I want my pH hovering that low. My math says I'm down to TA 96.2 ppm at this point although I haven't tested to confirm.
You are correct. If you stay in the lower pH range, your pH will rise much quicker due to increased carbon dioxide outgassing and you get the added benefit of a greater reduction in TA from the acid additions. Just be careful not to take the pH down too low.
The pH will take longer to rise the higher it gets.
The pH will take longer to rise the higher it gets.