Heavy scaling on the plates of my cell.

[Gregadaka]

If your fill water has a TA of 60 how is your pool TA getting to 160? And you say it has risen from 110 to 160?

Have you added any alkalinity increaser, baking soda, borax, soda ash or washing soda to the pool?

Even worse - 18 days it was 260!..

 

[mknauss]

That added 40 ppm of TA. Keep your pH in the 7's, the TA will fall.

 

[ajw22]

A couple of months ago, I bought Muriatic acid, thinking it was the same as CYA... I had my ignorance corrected on this forum - but by then, the pH was 6.2. I fixed the pH with 6 lbs sodium Bicarb (Arm & Hammer). Could that be the problem?

6 lbs of baking soda in your 10,500 gallons will raise TA by 41 and ph by 0.1. That was not enough to raise your TA over 200 ppm.

For future reference:

• Baking Soda = big TA change, small pH change
• Borax = Big pH change, small TA change
• Soda Ash/Washing Soda = big pH change, big TA change.

How new is your TF-100 kit?

See Notes in TA instructions...

• Sometimes a static electric charge can build up on the R-0009 dropper bottle tip, causing the drops to be smaller than usual and making the test read higher than actual. You can prevent this by wipping the tip of the dropper bottle with a damp cloth or tissue before you start and after each drop.
• Hold the dropper bottles vertically and squeeze gently, so that drops come out slowly and seem to hang on the tip of the dropper bottle for a moment before falling.

Total Alkalinity

A drop-based test used to measure the alkalinity in water. Alkalinity helps serve as a … Read more…

www.troublefreepool.com

 

[Gregadaka]

Okay, I'll make a quick correction, with apologies here... I used Arm & Hammer washing soda - 100 % Sodium bicarbonate - 12 lbs of it, not 6 lbs, but 12 lbs.

 

[mknauss]

That is a much bigger effect. About 130 ppm TA and 4 points of pH. In the future, never add that much of any chemical at once. And preferably never use soda ash. It is taking a sledge hammer to the issue.

Regardless. Keep your pH in the 7's. The TA will fall. Or follow the process to lower your TA in TA - Further Reading

 

[mgtfp]

Okay, I'll make a quick correction, with apologies here... I used Arm & Hammer washing soda - 100 % Sodium bicarbonate - 12 lbs of it, not 6 lbs, but 12 lbs.

Just to avoid any remaining confusion: Did you want to write "I used Arm & Hammer washing soda - 100 % Sodium Carbonate" (No "Bi"...)?

Washing Soda is Sodium Carbonate (Na₂CO₃),
Baking Soda is Sodium Bicarbonate, also called Sodium Hydrogen Carbonate (NaHCO₃).

The "Bi" is a bit confusing, historical legacy from an outdated naming system.
Wikipedia: "The prefix bi in bicarbonate comes from an outdated naming system and is based on the observation that there is twice as much carbonate (CO₃) per sodium in sodium bicarbonate (NaHCO₃) as there is in sodium carbonate (Na₂CO₃)."

 

[Gregadaka]

Good question. I've wondered about Arm & Hammer "Baking Soda". On their website, it's listed under "industrial". According to them, it's sodium bicarbonate.

C&D Corporate

churchdwight.com

 

[Gregadaka]

That is a much bigger effect. About 130 ppm TA and 4 points of pH. In the future, never add that much of any chemical at once. And preferably never use soda ash. It is taking a sledge hammer to the issue.

Regardless. Keep your pH in the 7's. The TA will fall. Or follow the process to lower your TA in TA - Further Reading

Thanks!
Lesson learnt...
It's so good to have a forum like this to go to to

 

[mgtfp]

Good question. I've wondered about Arm & Hammer "Baking Soda". On their website, it's listed under "industrial". According to them, it's sodium bicarbonate.

C&D Corporate

churchdwight.com

So, you did add Baking Soda, and not Washing Soda?