Muriatic Acid did not lower Alkalinity

Problems relating to pH and total alkalinity.
Increase ph, increase TA. Reduce pH, reduce TA.
pH chemistry advice and techniques for the pool.
andre747
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Muriatic Acid did not lower Alkalinity

Postby andre747 » Mon 29 Aug, 2016 18:46

Hi everybody. I need help. Here are the steps i did. Took over a pool with high chlorine, no alkalinity, no PH, no CYA and hard 400 ppm. Waited for chlorine to go down to 4 ppm. Added 30 lbs of baking soda and alkalinity +. Finally increased PH to 7.2 and AK to 140 ppm. So I decided to add muriatic acid to lower AK but AK went up to 200! What did I do wrong? Thank you. Andre


Denniswiseman
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Re: Muriatic Acid did not lower Alkalinity

Postby Denniswiseman » Tue 30 Aug, 2016 05:00

How are you testing? Pool stores and strips don't give accurate readings.
You probably tried to do to much in one go as there is no way muriatic acid didn't reduce your TA
Check out Pool Maths
I worked out you needed 432 ounce (27 pounds) of baking soda not 30 to give you 80ppm TA. You didn't need to add the alkalinity +
I suggest you raise your CYA to the recommended level for your pool in the Chlorine / CYA Chart but wait a few days before testing as it takes a while to dissolve

Check out the recommended Pool Levels for your pool
andre747
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My Pool: Rectangular, 23K gallons, 60 GPM pump, Hayward C17502 Cartridge, Salt Based

Re: Muriatic Acid did not lower Alkalinity

Postby andre747 » Tue 30 Aug, 2016 06:16

Thank you Dennis for your reply. I use drops kit not strips. I am in the *spamm* islands and it is hard to get products here. I did order a Lamotte 7022-01 test kit but it will take at least a week before it gets here. Should i just wait until the test kit gets here? Thank you again for your help.
Denniswiseman
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Posts: 2594
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My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Muriatic Acid did not lower Alkalinity

Postby Denniswiseman » Tue 30 Aug, 2016 10:08

You could recheck your numbers again and try the pool maths
andre747
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Posts: 6
Joined: Mon 29 Aug, 2016 18:38
My Pool: Rectangular, 23K gallons, 60 GPM pump, Hayward C17502 Cartridge, Salt Based

Re: Muriatic Acid did not lower Alkalinity

Postby andre747 » Tue 30 Aug, 2016 18:49

Thanks Dennis. I re-check and TA still around 220 ppm. Nobody here (pool store) can test CYA. I am dying to get my test kit.
Denniswiseman
Pool Industry Leader
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Posts: 2594
Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Muriatic Acid did not lower Alkalinity

Postby Denniswiseman » Wed 31 Aug, 2016 04:38

Use the pool maths and use muriatic acid to reduce the TA. This will reduce your PH as well which you can raise by aeration
I use a large pond aerator but so long as you can spray from your return jets into the air it will do the same thing
andre747
I'm new here
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Posts: 6
Joined: Mon 29 Aug, 2016 18:38
My Pool: Rectangular, 23K gallons, 60 GPM pump, Hayward C17502 Cartridge, Salt Based

Re: Muriatic Acid did not lower Alkalinity

Postby andre747 » Thu 08 Sep, 2016 05:08

I finally got a decent test kit 7022-01 from Lamotte. I added muriatic acid to reduce TA and now it is at 420. I really don't get it. Why is it going up not down?
By the way after i saw hardness at 1,320 i tested hardness twice and tested my tap water to make sure i am doing it right which is 100 ppm.
CH 4
PH 7 ppm
TA 420 ppm
Hardness 1,320 ppm
CYA 50.

Thank you for your help.
Denniswiseman
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Posts: 2594
Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Muriatic Acid did not lower Alkalinity

Postby Denniswiseman » Thu 08 Sep, 2016 06:01

Hi Andre
I see by your profile that your pool is salt based, does it have a SWG if so you need to raise your CYA to 70-80
Is your CH of 4 Chlorine? and how do you maintain it
Is Your hardness, calcium hardness, if so it appears that it is being raised with your TA
Are you sure you are using Muriatic Acid (hydrochloric Acid) as it seems that hardness and alkalinity is rising with what ever you are adding.
By adding acid you are making it more acidic less alkaline (impossible for it to go up)
The only other way to get the pool in balance is to do partial drain and refills but I would definately check your Muriatic Acid (hydrochloric Acid)
andre747
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Joined: Mon 29 Aug, 2016 18:38
My Pool: Rectangular, 23K gallons, 60 GPM pump, Hayward C17502 Cartridge, Salt Based

Re: Muriatic Acid did not lower Alkalinity

Postby andre747 » Thu 08 Sep, 2016 18:07

Sorry i forgot to answer your other question. Salt base with Hayward Aqua Rite 15 cell. Salt is at 3300 ppm
Denniswiseman
Pool Industry Leader
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Posts: 2594
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Location: United Kingdom

Re: Muriatic Acid did not lower Alkalinity

Postby Denniswiseman » Fri 09 Sep, 2016 02:19

That is the only question answered so you need to raise your CYA to 70-80
If you are going to do a drain and refill you would raise it after
andre747
I'm new here
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Posts: 6
Joined: Mon 29 Aug, 2016 18:38
My Pool: Rectangular, 23K gallons, 60 GPM pump, Hayward C17502 Cartridge, Salt Based

Re: Muriatic Acid did not lower Alkalinity

Postby andre747 » Fri 09 Sep, 2016 10:35

Thank you. I'll raise CYA to 70-80.
The muriatic acid is definitely hydrochloric 31.45%
Is your CH of 4 Chlorine? YES. and how do you maintain it. Maintained by the SWG Aqua Rite set on auto at 30.
Is Your hardness, calcium hardness? YES

Water is very expensive here but we'll consider replacing some of it. How much of the 23,000 gallons would you suggest?

Thank you for your help.
Denniswiseman
Pool Industry Leader
Pool Industry Leader
Posts: 2594
Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Muriatic Acid did not lower Alkalinity

Postby Denniswiseman » Fri 09 Sep, 2016 12:51

Don't raise the CYA untill any drain and refill is done
You may wish to give Muriatic acid another go as your previous dosing may have thrown things haywire. Test before doing it and the test the next day to see the difference
If you are draining I think 2/3 of the water

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