Total Alkalinity R-0009 question TF100/speedstir

[AB]

Hi, I am using the TF100 and speedstir kit.

When performing the total alkalinity test, after about the 8th drop when i speedstir the solution it initially turns red, then back to green once it stops stirring.

It is only after the 14th drop that it stays red after stirring stops.

My question is, should the reading be 8*10 = 80 or 140? Do I use the "initial red" or "stays red" to indicate completion of the test?

Thanks so much,Aaron

 

[257WbyMag]

Once it stays red, that is your result.

 

[chem geek]

The initial red is from localized portions of the water sample where you've added the acid drops exhausting the TA buffer, but as soon as that mixes with the rest of the sample, the pH rises back up to return to green. It's an indication that you're getting closer to the end, but you probably noticed that more and more of the sample seemed to "turn" as you got even closer to the end. It's only when the entire sample gets mixed with the drops you've been adding and stays red that this is the end of the test. The next drop you add should not change the hue and you don't count that drop (i.e. you count up to and including the last drop that causes a change in appearance).

 

[AB]

awesome...thanks for the quick response! Looks like I have a little problem since T/A is 140!! (

 

[Richard320]

awesome...thanks for the quick response! Looks like I have a little problem since T/A is 140!! (

Not really. What does the pool look like? What are the other numbers? If you have high pH and high CH, that high TA can push the CSI into scaling territory. If CSI is okay, the TA will come down eventually if you keep adjusting pH.

It's only a problem if you're at risk of scaling; there's no health concern with it; the high TA came from the tap water, and you bathe in the same stuff and drink it!

 

[AB]

Richard,
ph is between 7.8 and 8.2 (cant quite determine the "pink" vs "orange" differentiation on the test kit). CYA at 40. I will check the CH now.
Thanks, Aaron

 

[Bama Rambler]

Keep in mind that as you lower your pH (which you should do now) your TA will come down. There's no rush in adjusting it.

Go ahead and post a full set of test results.

 

[AB]

Hi guys,
my results:
CH = 190
CYA = 40
T/A = 140
ph = 7.9

Thanks for your help...pls let me know if I need to give you more results.
Aaron

 

[JasonLion]

Assuming you aren't using trichlor tablets, you want to lower PH to around 7.2 any time it gets to 7.8, at least until TA comes down some more.

If this is a plaster/pebble pool, you should raise the CH level to at least 250.

You didn't say what your FC and CC levels were.

 

[AB]

Sorry! That would help. Yes, it is a plaster pool.
FC = 8.5
CC = 1

I just put 15 oz muriatic acid in the pool so I will check pH tomorrow morning and let you know.
Thanks, Aaron