Interpreting color changes in TF-100 calcium and TA test

Copernicu

Bronze Supporter
Jul 22, 2020
22
Phoenix, Arizona
Hello, I received my TF-100 test kit and finally did my first tests.

On the calcium test, at drop 15, the color was purplish/bluish but not quite. At drop 16, it was blue. At drop 17, seemed like it was maybe more blue, but I'm not 100% sure. How should this be interpreted?

Similarly, on the TA test, it looked red at drop 12 but possibly more red at drop 13. Could be my vision, lol. How should this be interpreted?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
19,496
Northern NJ
One drop +/- does not make a difference in your water chemistry.

Add drops until you see no change from the last drop and subtract that drop from the count.

So your CH is 160 or 170 and your TA is 120 or 130. Either one is about the same.
 

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
14,456
Evans, Georgia
I'll tell you how I see my TA test-
It goes from green to reddish at x drop...
One more drop makes it look kinda Barbie pink...
One more drop makes it HOT BARBIE PINK!...
Another drop doesn't change it and its still HOT BARBIE PINK!! I count all the drops *except* this last one.

Maybe this will help you :)

Maddie
 
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Copernicu

Bronze Supporter
Jul 22, 2020
22
Phoenix, Arizona
Thank you for the responses.
One drop +/- does not make a difference in your water chemistry.

Add drops until you see no change from the last drop and subtract that drop from the count.

So your CH is 160 or 170 and your TA is 120 or 130. Either one is about the same.
Thank you..

I'm confused about the multiplier for CH.

You used 10x. That is the same as the TF-100 youtube video (
)

But the instructions in the TF-100 test kit I just received say 25.

Can you confirm the correct number?
 

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
14,456
Evans, Georgia
You can do the test with either 25mL of pool water (my preference) or 10mL of pool water.

If you use 25 you multiply by 10
If you use 10 you multiply by 25.... hence you can see why I'm lazy and use 25 mL. :)

Maddie
 
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ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
19,496
Northern NJ
What Maddie said.

I didn't know if you used a 10ML or 25 ML sample and had a 50/50 chance of being correct so I used what I do, 25 ML sample and multiply by 10.
 
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HermanTX

Gold Supporter
May 20, 2020
524
Katy TX
But if I understand the video, if you use 25ml for the CH test, you must start with 20 drops of R-0010 followed by 5 drops of R-0011L. However with the 10ml sample you only use 10 drops of R-0010 and 3 drops of R-0011L. Therefore you use less reagents per test with the 10ml sample. Also, the use of R-0012 will also need to be higher with the 25ml sample for the same end result of CH because you are only multiplying by 10x vs 25x in the 10ml sample. for CH of 300, it would be 30 (30 x 10) drops in the 25ml sample and only 12 (12 x 25) drops with the 10ml sample. Does this make sense?
 

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
14,456
Evans, Georgia
Yup I hear ya. Long ago the directions came for everyone to use the 25 mL amount of pool water. Then later it was tested that using 10 worked also (with less reagents, obviously).

I'm old and just remember how I was initially taught/learned so I stick to that formula. You'll just have to decide for yourself which to use, and I would say use one way consistently.

Maddie
 
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