TA level

[essikr]

IG vinyl 16X32 pool problem getting the TA down! New liner installed this year treated water using BBB. I added stabilizer and everything looks good except the total alkalinity.I use the Taylor 2006 test kit and my current numbers are:
FC= 3.5
CC = 0
PH = 7.2
TA = 175
CH = 225
CYA = 30
The TA has gone from 190 to 125 after adding 2 gal. of muratic.It went back up in two weeks to 175 .added another gal of muratic and it went done to 135.It is now back up to 175. Should I add more muratic or is something else happening?

[aylad]

What are you using to bring your pH back up after the acid additions?

Janet

[essikr]

Using Borax on two occasions one box each time .I believe there is a little over 4#'s in a box.I have been using BBB method for several years now,this is the first time I had to bring the TA down . I have a good supply of baking soda to bring it up if necessary!

[aylad]

Doesn't sound like you're gonna need the baking soda anytime soon!! Just wanted to make sure that you're using Borax instead of washing soda, which would bring the TA back up and defeat the purpose of the muriatic. The boxes are next to each other at my grocery store, and look similar except that they are different colors. Only thing I know to do is to add more muriatic and repeat your ratcheting process until you get it where you want it. Just make sure that you keep a close eye on your pH--you don't want it to get below 7.0 or you risk damaging your liner. Make sure you raise it up enough between acid additions so that after the addition, it's still 7.0 or higher. Is your fill water high in TA? That may be one reason why it's so high and is coming back up if you're having to refill frequently.

Sorry I don't have a more concrete answer for you, but sometimes we just have to "treat the symptoms", even when we don't understand the cause!!

Janet

[chem geek]

In the procedure to lower the TA, you simply continue aerating without adding more acid in order to raise the pH with no change in TA. Even adding Borax will raise both the pH and the TA. It is true that it will raise the TA by half as much as soda ash, but it will still raise it; aeration won't.

[CarlD]

I dunno...a T/A of 175 with a CH of 225 in a vinyl pool just isn't anything to worry about. It probably will have no effect at all.

Don't sweat it, don't mess up your other chemistry unless you are having troubles maintaining your desired pH.

Only then should you worry about lowering your T/A.

Vinyl pools with low CH levels are VERY tolerant of T/A levels well above the "maximum" of 125ppm. When it gets over 200ppm, then you need to act.

Only when the T/A approaches 200ppm and the CH is past 400ppm, approaching 500ppm do you have a shot of scaling and cloudy water. But you shouldn't at these levels.