Types of total alkalinity tests

[bill3956]

Are there other types of TA tests? Using Taylor 2006C and following the TA test method here. My “former” pool service consistently got a lower TA number than I did and as a result was frequently adding baking soda. As a result I was adding MA to lower Ph and keep CSI in line. Very counterproductive.

When testing chlorine they got 3 even when it was higher so I know they were using the color test if that gives some insight as to what method they might be using. Thanks.

Bill

 

[Donldson]

The chlorine thing just sounds like they were using an OTO test and hurrying through it. "Topped out? 3 ppm it is. Next pool!" That business is all about quantity and price, not quality and value. I found that out the hard way ?

My guess would by they are using Adjusted Alkalinity which is adjusted for CYA level. Not much point to it but some pool stores and services still feel the need to use it.

 

[bill3956]

Thanks. Yesterday I got 110 and they got 80. They threw in 5 pounds baking soda. TA was 140 this morning. That’s about right for my pool based on Pool Math. Next week is their last visit.

Bill

 

[mknauss]

Now you get to add acid to lower the pH which is rising fast because of the high TA.

Do not chase a TA. Manage the pH into the 7's and the TA should settle when the pH stabilizes.

 

[bill3956]

Thanks for the confirmation that my approach is correct. Been adding acid to keep CSI within reason. High CH 625 has not helped the high TA and corresponding CSI. Slowly working to get all the numbers where they should be, but the water looks great thanks to this forum.

Bill

 

[mknauss]

With elevated CH it is best to keep adding acid to get TA down in the 60 or 70 range. They adding baking soda was chemically stupid.

 

[bill3956]

They’ve never tested CH that I know. Pool new last September. From what I’ve read I keep expecting CH to decline at some point as the plaster cures. Although I don’t think there has been any real water loss. Maybe the summer with evaporation it will go down some. Fill water around 200.

Bill

 

[mknauss]

CH will not go down with evaporation. To lower it you must drain pool water and then add water with less CH. With your fill water, it will continue to rise when topping up from evaporation.