Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 11 of 11

Thread: Experience with AA & a couple questions (Sorry for the long post)

  1. Back To Top    #1

    Join Date
    May 2014
    Location
    Vienna, VA
    Posts
    36

    Experience with AA & a couple questions (Sorry for the long post)

    So, our pool is about 27 years old and I believe it has the original plaster. Supposedly it was painted 8+ yrs ago rather than being replastered so the surface is marginal at best. There are areas where the paint has come off, some black spots and metal stains on the floor and walls. After confirming there’s metal in the water (.3ppm CU & .8ppm iron) I decided to try the AA treatment. I was pressed for time to get this down so I kinda rushed things and “rounded” my numbers but assumed I was in the ball park. Despite knowing that FC should be 0, I started when it was down to 1.5 (and figured I'd use a little extra AA). The pH was also 7.5. I dumped a gal of MA to bring the pH down -- although a gal was probably a little more than I needed, I assumed as long as I was below 7.2 I’d be ok

    I dumped in about 80 oz of Polyquat 60 (again, probably a little more than I needed but figured it couldn’t hurt).

    I started with 4lbs of AA (using the ratio of 1lb/10000g) but the change was barely perceptible. Knowing there was some residual FC I went all in and dumped my entire 8lb bucket of AA and lightly scrubbed all surfaces with my ss brush. I also threw a Culator 4.0 in the pump basket for good measure (even though there are mixed reviews on the effectiveness)

    Last night (24hrs into the process) I was surprised that while the stains were lighter, it wasn’t 100% effective. I tested the levels and FC=0 as expected, pH=6.8, TA=60.

    Assuming that was the best it was gonna look I started to dial the chems back in. I added a gal of Jacks Purple stuff (ouch that stuff is expensive!), a gal of 10% bleach and 7lbs of Soda Ash (recommended dosing by PoolMath). This morning I was really surprised that the pH was still 6.8 after all that soda ash.

    Couple questions:
    1) For the AA treatment, it is less effective if the pH is lower than 7.2?
    2) If pH wasn’t the problem, then with a residual FC of 1.5 is double the dose of AA still too little?
    3) Why didn’t my pH rise since the Soda ash addition last night? According to PoolMath for my starting pH of 6.8 and TA of 60, I needed 6lbs-15oz of Soda ash for pH of 7.2 The Soda Ash I used was left behind by the previous owner and was slightly “chunky” as if it had seen some humidity. I chopped it up and assumed that wouldn’t make a difference – would it??

    Thanks!!
    -Mike
    40K gallons, IG, plaster, circa 1987, 60sqft Crystal Water DE filter, Hayward Ecostar VS pump, SWG, attached spa w/spillway, 2 skimmers.

  2. Back To Top    #2

    Join Date
    Oct 2013
    Location
    Chapin, SC
    Posts
    1,141

    Re: Experience with AA & a couple questions (Sorry for the long post)

    My understanding is that pH of 6.8 is the lowest the test will show, it could be considerably less (gallon of MA?) My pool math says you quadrupled the proper dosage That should have taken your pH down to about 6.4? That would have required a little over 14 lbs of Soda ash or 455 lbs of borax to get it up up to 7.2. Again, that's my understanding I'll let the experts weigh in on this.
    Pool size: 24000gal inground Vinyl-Taylor k-2006 and k-1766 test kits and-speed stir
    Intermatic P1353ME digital timer w/freeze sensor
    CircuPool Si-45 SWCG System
    Polaris 280 vacuum/Polaris PB4-60 boost pump
    Pentair IntelliFlo VS 3hp Pump--Pentair sand filter

  3. Back To Top    #3
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Experience with AA & a couple questions (Sorry for the long post)

    I get that the gallon of acid should have only lowered the pH from 7.5 to about 7.0 assuming a starting TA of around 70ppm in a 40k pool. Not sure where timerguy got his numbers though (you can not rely on the Effect of Adding Pool Chemicals section for large pH changes).

    I agree that anything below 6.8 may show as 6.8, but I do not understand how it got so low in the first place.

    I also get that it would require 8.125 pounds of soda ash to raise from 6.8 to 7.2 with a TA of 60 ... so not sure why you got a different amount.

    Disregard, I had Borates set at 50
    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!

  4. Back To Top    #4

    Join Date
    May 2014
    Location
    Vienna, VA
    Posts
    36

    Re: Experience with AA & a couple questions (Sorry for the long post)

    I just plugged it into Pool Math and I must be making some mistake because it's telling me to use 1gal 1cup of MA to drop pH from 7.5 to 6.8 with TA at 60 for a 40Kgal pool -- you scared me when you said I quadrupled the dosage
    40K gallons, IG, plaster, circa 1987, 60sqft Crystal Water DE filter, Hayward Ecostar VS pump, SWG, attached spa w/spillway, 2 skimmers.

  5. Back To Top    #5

    Join Date
    Oct 2013
    Location
    Chapin, SC
    Posts
    1,141

    Re: Experience with AA & a couple questions (Sorry for the long post)

    I got the numbers without putting in all the levels in PoolMath. After doing so, it was a .77 decrease resulting in 6.73 Which now shows needing almost 10lbs of washing soda or just over 19lbs of borax
    Pool size: 24000gal inground Vinyl-Taylor k-2006 and k-1766 test kits and-speed stir
    Intermatic P1353ME digital timer w/freeze sensor
    CircuPool Si-45 SWCG System
    Polaris 280 vacuum/Polaris PB4-60 boost pump
    Pentair IntelliFlo VS 3hp Pump--Pentair sand filter

  6. Back To Top    #6

    Join Date
    May 2014
    Location
    Vienna, VA
    Posts
    36

    Re: Experience with AA & a couple questions (Sorry for the long post)

    Regardless, it sounds like I must have goofed on my Pool Math entries so I likely just need to add more Soda ash/borax to bring my pH back up.

    But, any thoughts on the effectiveness of the AA? Given my old plaster/paint are my expectations too high for all metal staining to disappear given the about of AA I added? -- Again, the stains definitely lightened but they're still noticable.

    From reading the AA thread it seemed that people were all pretty happy with the results, so I was kinda expecting everything to clean up.
    40K gallons, IG, plaster, circa 1987, 60sqft Crystal Water DE filter, Hayward Ecostar VS pump, SWG, attached spa w/spillway, 2 skimmers.

  7. Back To Top    #7
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Experience with AA & a couple questions (Sorry for the long post)

    Quote Originally Posted by timerguy View Post
    I got the numbers without putting in all the levels in PoolMath. After doing so, it was a .77 decrease resulting in 6.73 Which now shows needing almost 10lbs of washing soda or just over 19lbs of borax
    You can NOT use the Effects of Adding Chemicals like that as I said above.
    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!

  8. Back To Top    #8

    Join Date
    Oct 2013
    Location
    Chapin, SC
    Posts
    1,141

    Re: Experience with AA & a couple questions (Sorry for the long post)

    That WASN"t from the effects of adding chemicals That was from the recommended dosage after posting the numbers in pool math.

    - - - Updated - - -

    That WASN"t from the effects of adding chemicals. That was from the recommended dosage after posting the numbers in pool math. Except for the MA addition.
    Pool size: 24000gal inground Vinyl-Taylor k-2006 and k-1766 test kits and-speed stir
    Intermatic P1353ME digital timer w/freeze sensor
    CircuPool Si-45 SWCG System
    Polaris 280 vacuum/Polaris PB4-60 boost pump
    Pentair IntelliFlo VS 3hp Pump--Pentair sand filter

  9. Back To Top    #9
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Experience with AA & a couple questions (Sorry for the long post)

    Quote Originally Posted by timerguy View Post
    Except for the MA addition.
    Exactly my point. Read the note in PoolMath.
    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!

  10. Back To Top    #10

    Join Date
    Jul 2011
    Location
    Austin, TX
    Posts
    60

    Re: Experience with AA & a couple questions (Sorry for the long post)

    As for the metal stains, I don't believe AA will work on copper. You should test the stains to know for certain what you're dealing with to ensure the best outcomes.


    16,000g in-ground plaster pool, attached spa, BBB, DE Filter, SWG

  11. Back To Top    #11
    smforte's Avatar
    Join Date
    Sep 2013
    Location
    Montgomery,Al
    Posts
    668

    Re: Experience with AA & a couple questions (Sorry for the long post)

    Did you try a vitamin c pill first on the stain to confirm the metal stain was from iron? I have iron stains and vit C removes it like magic.
    Montgomery, AL
    27000 16 x 36 IG, Vinyl, Grecian, Hayward Sand filter, 1 HP Pentair whisperflo motor, Aqua Genie filter not by choice, no extra jets, Dolphin s300i robotic cleaner,Taylor K 2006 test kit, speed-stir which I couldn't live without!

Posting Permissions

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