Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 18 of 18

Thread: Low TA / high pH

  1. Back To Top    #1

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Low TA / high pH

    I have been keeping an eye on my TA, which has been steady around 70 for a while. Our pH creeps us, leading me to have to add acid once a week or so. It has just finished raining here and the past few days I have been watching our pH creep up, preparing to add some acid today possibly as it is now at 7.7 I just checked our TA assuming it was still at 70, but it is now at 60.

    What do you do when your pH is high and needs fixing, but your TA is low and needs fixing as well? Do I shoot to increase my TA first at this point? Or since it just finished raining, should I leave everything alone and wait and test again tomorrow and see where we are at?

    FC: 4
    TA: 60
    pH: 7.7
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

  2. Back To Top    #2
    Mod Squad JohnT's Avatar
    Join Date
    Apr 2007
    Location
    SW Indiana
    Posts
    9,086

    Re: Low TA / high pH

    What is your CH?
    TFP Moderator
    20K Gallon 20X36 Vinyl Inground
    Hayward S244T Sand Filter with 1HP Whisperflo Pump. Liquidator C-201 and Solar Heat

  3. Back To Top    #3

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Re: Low TA / high pH

    Just tested CH the other day and was about 160 (vinyl pool). We're not terribly concerned with CH for a vinyl though, right?
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

  4. Back To Top    #4

    Join Date
    Jul 2013
    Location
    Central New Jersey
    Posts
    55

    Re: Low TA / high pH

    Well every time you lower the pH even with muriatic acid it slow lowers your TA. Check out the pool calculator to get an idea of how much each addition of acid will lower it. You'll just have to add baking soda when ever you want to raise your TA back up. If your pool sees heavy use, lots of splashing or has a water fall, or a suction side leak the aeration could also be causing your pH to raise and your TA fall. You can't stop the use well you could but that wouldn't be any fun, but you can possible change the others, though they probably aren't your problem.
    26K Gallon, IG vinyl
    1.5 HP Hayward Super Pump, DE Filter 36 SqFt
    Older than time TELEDYNE LAARS HEATER (removed from system for now)

  5. Back To Top    #5

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Re: Low TA / high pH

    Quote Originally Posted by uloset
    Well every time you lower the pH even with muriatic acid it slow lowers your TA. Check out the pool calculator to get an idea of how much each addition of acid will lower it. You'll just have to add baking soda when ever you want to raise your TA back up. If your pool sees heavy use, lots of splashing or has a water fall, or a suction side leak the aeration could also be causing your pH to raise and your TA fall. You can't stop the use well you could but that wouldn't be any fun, but you can possible change the others, though they probably aren't your problem.
    Yes, I do know the acid lowers the TA, which is not what I want to do at this point with a TA of 60, but I know increasing the TA with baking soda will also increase the pH, which is not what I want to do either. Just asking which I should treat in this case.
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

  6. Back To Top    #6
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Low TA / high pH

    I would leave the TA alone and see if it and the pH settle somewhere. You are fine going a little lower than 60ppm.

    Do you have a lot of aeration leading to the pH rise?
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  7. Back To Top    #7

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Re: Low TA / high pH

    Quote Originally Posted by jblizzle
    I would leave the TA alone and see if it and the pH settle somewhere. You are fine going a little lower than 60ppm.

    Do you have a lot of aeration leading to the pH rise?
    Nope. Not that I can think of. We haven't swam in weeks since it's been cool out and the pool temp dropped. It hasn't rained much the past few weeks other than some rain today and no water features.

    BTW, how much lower than 60 is fine and what happens if it goes below 60 and my pH is still high?
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

  8. Back To Top    #8
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Low TA / high pH

    What do you deem as "high" pH? There is nothing wrong with 7.7-7.8. If it stays there, just leave it. But lower it if it gets to the 8s.

    Just leave the TA alone and see what happens.

    I am wondering if you are trying to maintain a pH lower than you need to and that the pool may find a happy place with the pH in the upper 7s.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  9. Back To Top    #9

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Re: Low TA / high pH

    Quote Originally Posted by jblizzle
    What do you deem as "high" pH? There is nothing wrong with 7.7-7.8. If it stays there, just leave it. But lower it if it gets to the 8s.

    Just leave the TA alone and see what happens.

    I am wondering if you are trying to maintain a pH lower than you need to and that the pool may find a happy place with the pH in the upper 7s.
    Yeah, you may be right. Maybe my pool likes the pH a little higher. Whenever it hits around 7.7, I like to bring it down a bit to 7.6 or so, so I have some room to play with, but I'll just let it go this time and see what happens.

    Is it okay to close a pool with a low TA, like 60? We're closing on September 11, and I'm just wondering about that.

    I know it doesn't mention anything about adding algaecide in Pool School when closing, so I assume that is not recommended?? (It's probably more of a pool store thing to recommend adding that but want to make sure). I know we bring it to shock level before closing, just wondering about algaecide. If bringing it to shock level, there would be no need for algaecide if I am thinking correctly.
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

  10. Back To Top    #10
    Mod Squad JohnT's Avatar
    Join Date
    Apr 2007
    Location
    SW Indiana
    Posts
    9,086

    Re: Low TA / high pH

    Quote Originally Posted by suziequsie2945
    Just tested CH the other day and was about 160 (vinyl pool). We're not terribly concerned with CH for a vinyl though, right?
    Only if it's high, in which case you would need to keep your pH in the lower part of the range to avoid scaling.
    TFP Moderator
    20K Gallon 20X36 Vinyl Inground
    Hayward S244T Sand Filter with 1HP Whisperflo Pump. Liquidator C-201 and Solar Heat

  11. Back To Top    #11
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Low TA / high pH

    Is your water going to be below 60 degrees on Sept 11? If not, then you should not close yet.

    Did you read this:
    pool-school/closing_in_ground_pool

    It does say to use algaecide:
    PolyQuat - Add the startup (maximum) dose of PolyQuat according to package directions. I give it half an hour to mix with the pump running before starting to drain. While I am waiting for that I proceed with the next three steps.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  12. Back To Top    #12

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Re: Low TA / high pH

    Ok, I'm trying to understand the whole relationship between TA and pH, so please bear with me. To be honest, I'm a bit nervous of having TA on the low side (worried particularly about corrosion) when the recommended range is 80-120, but I know you guys know what you're talking about, so when you say 60 for TA is okay I believe you.

    Hopefully, you can tell me if I am understanding properly: What I am understanding is that TA is ONLY a measurement. A low TA will not cause corrosion in and of itself but if the low TA causes your pH to be off significantly, the low pH is what will actually cause the corrosion. Is this correct? Therefore, if I have a low TA, but my pH is fine, there is no need to worry about it because the pH, the thing that can CAUSE the corrosion (not the TA) is within normal range. I want to make sure I understand this.

    Another thing I am afraid of is wrinkling and such of my liner with such a low TA and am hoping you can put my mind at ease regarding this as I think if the TA stays so low I will have to address it before we close the pool so it doesn't cause any damage to the liner, or anything else.

    (BTW...I am SO very grateful for you guys and this site. This was our best pool year by far and I couldn't have done it without you guys. If it wasn't for me finding you, I would probably be in the vicious cycle of the pool store merry-go-round. I have never taken care of the pool at all (my husband always did it) but this year he has been working like crazy so I took on the job of the pool, and because of you and your advice, it has never been clearer. Wish we found you sooner!)
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

  13. Back To Top    #13
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Low TA / high pH

    I think you got it. TA buffers the pH from changing wildly with chemical additions. Too low and the pH swings, too high and it pulls the pH up. 60ppm is fine, although may not want to go much lower if at all. Not sure why this would affect the liner.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  14. Back To Top    #14

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Re: Low TA / high pH

    Quote Originally Posted by jblizzle
    I think you got it. TA buffers the pH from changing wildly with chemical additions. Too low and the pH swings, too high and it pulls the pH up. 60ppm is fine, although may not want to go much lower if at all. Not sure why this would affect the liner.
    Ok, I will keep my eye on the TA. That brings me back to my original question, if the TA drops any lower, and my pH is more on the higher side where I don't want it to go up, what do I do? Would I add some acid first to drop the pH to say 7.4/7.5, and then add baking soda to raise the TA?
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

  15. Back To Top    #15
    linen's Avatar
    Join Date
    Jul 2010
    Location
    Twin Cities, MN
    Posts
    8,649

    Re: Low TA / high pH

    Quote Originally Posted by suziequsie2945
    Would I add some acid first to drop the pH to say 7.4/7.5, and then add baking soda to raise the TA?
    Yep, you got it...though in your case, I wouldn't drop ph until it goes above 8.0
    TFP Expert who uses Pool School and my TF100 test kit along with PoolMath for my: Round 11K gallon AGP with deep end, 20" sand filter, Matrix 1hp 2spd, 6 2ftX20ft solar panels (and solar cover!), Intex SWCG (copper bars disconnected) and a Rubadub hot tub (chlorine). The SLAM process is not finished until: 1. CC < 0.5 ppm, 2. An OCLT < 1.0 ppm and, 3. The water is crystal clear.

  16. Back To Top    #16

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,077

    Re: Low TA / high pH

    but I know increasing the TA with baking soda will also increase the pH
    I can't see in the thread that this was ever corrected. Baking soda has virtually no effect on pH.

    OP, you might be overthinking the TA a bit. Your pH is the more important parameter and should always be in the 7's. Lower it if it get's above that and control your TA with baking soda if it needs to be raised up into the guidelines suggested in Pool School

    Folks live with a wide range of TA.
    (worried particularly about corrosion)
    Neither high TA or low TA is "corrosive" as long as you stay within the guidelines in Pool School.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  17. Back To Top    #17

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Re: Low TA / high pH

    Quote Originally Posted by duraleigh
    but I know increasing the TA with baking soda will also increase the pH
    I can't see in the thread that this was ever corrected. Baking soda has virtually no effect on pH.

    OP, you might be overthinking the TA a bit. Your pH is the more important parameter and should always be in the 7's. Lower it if it get's above that and control your TA with baking soda if it needs to be raised up into the guidelines suggested in Pool School

    Folks live with a wide range of TA.[quote:30y2yl7q] (worried particularly about corrosion)
    Neither high TA or low TA is "corrosive" as long as you stay within the guidelines in Pool School.[/quote:30y2yl7q]

    Thank you all very much. I think I am definitely overthinking the TA, but when I noticed I was out of Pool School's recommended range for TA, range of 70-90+ and way out of the range of my test kit's recommended limits which has a range of 100-120, I got a little nervous.


    I am taking all of your advice. I have left the pH and TA alone and all seems to be stabilized right now. Like jblizzle said, I guess my pool likes my pH where it has been and I have been intervening when I shouldn't be!! I'm learning
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

  18. Back To Top    #18

    Join Date
    May 2013
    Location
    New Jersey
    Posts
    176

    Re: Low TA / high pH

    Quote Originally Posted by linen
    Quote Originally Posted by suziequsie2945
    Would I add some acid first to drop the pH to say 7.4/7.5, and then add baking soda to raise the TA?
    Yep, you got it...though in your case, I wouldn't drop ph until it goes above 8.0
    Thank you
    7+ years, inground, 25,000 gallon, vinyl, sand filter.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •