Just got TF-100, something not right

ea3421

Member
Jun 14, 2020
10
Woodmere, NY
I just received and tested using the TF-100 from tftestkits.net

Something isn't right --

CH
I tested the CH as per the instructions and the reading was 1025 (my last test in the pool store a week ago was 377ppm). I then tested the buffer solution (which is supposed to be 200ppm) and the measurement came back at 575ppm. Something's clearly not right.

ALK
the measure was 110ppm in the pool store a week ago -- but 290 as per the test.... When testing the buffer solution, it took about 40 drops of R-0009, so that's TA 400, and the buffer solution is supposed to be TA 100ppm.

Is there something wrong with the test kit?

Thanks
 

Texas Splash

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Welcome to TFP and congrats on testing your own water. Remember it's not uncommon to see some wid disparities between your testing and the pool store which is exactly wy we test our own water. That said, let's make sure of a couple things:
1. Do both the TA and CH test against your tap water as a test.
2. CH should be a 10 ML water sample, 10 drops of #10, 3 drops of #11, then each drop of #12 is 25 ppm until it turns a light baby blue. Make sure to go past the purple to baby blue.
3. The TA should be a 25 ML water sample, 2 drops of #7, 5 drops of #8 (should turn green), then each drop of #9 is 10 ppm. So 8 drops would be a TA of 80 for example.

Is that how you've been doing it? What does your tap water show?
 

duraleigh

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Is there something wrong with the test kit?
Probably not.

1. Pool Store tests are completely irrelevant.

2. CH Test - review your method (don't repeat the test just yet but review your sample size, correct reagent etc. Are you using 25 ml sample?

3. TA test - Follow the instructions on the sheet carefully. When the reagent R-0009 is brand new, it has a tendency to react statically with the bottle and the drops "jump" off the tip and are too small. Wipe down the dropper tip between each drop with a damp cloth. It'll only last a week or so.
 

ea3421

Member
Jun 14, 2020
10
Woodmere, NY
CH -
I also purchased and am testing against the CH standard solution which is 200ppm. Yes, I loaded the 40ml vial up to 10ml (as per instructions , and not up to 25ml). Then 10 drops of R-0010, then 3 drops of R-0011L. Mix. It turned red. Then added/mixed R-0012 until it turned blue. It took 23 drops, so the measure for the standard solution is 575ppm, and it's supposed to be standardized to 200ppm. When testing my pool, it is also very high, and 1025ppm.

TA -
Similar story. I followed the instructions as per the laminated instructions that came with the TF-100. I ran both of these several times, very carefully, exactly as per instructions.
 

duraleigh

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Not yet on the video. Confirm that you are wiping the dropper tip with a damp cloth between each drop.
 

ea3421

Member
Jun 14, 2020
10
Woodmere, NY
On the TA test, I did not wipe the dropper tip with a damp cloth between each drop the 2nd and 3rd time that I tried to run it the test -- I didn't notice a difference from the first time I ran it when I did wipe with a damp cloth. I can try to do it over. I do agree that for this test, the drops seem to jump off and may be too small.

But what about the CH test? It seems as though I followed directions perfectly.
 

duraleigh

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Don't beat yourself up doing it (TA test) over and over but wiping that dropper tip is pretty essential on a brand new kit. I would like to get that TA test resolved and then talk about CH..........I am frankly puzzled by the CH test and they are two completely separate issues but let's take them one at a time.
 

ea3421

Member
Jun 14, 2020
10
Woodmere, NY
You are right, my FC is definitely very high. I have a SWG generator and right now the pump runs 24x7. The pool store showed it was 11ppm.

Putting that aside though, I am testing and standard solution sent by tftestkits (not my pool water) and it's not coming out correctly. Let me take a video of the TA test, and let's go from there.
 

Texas Splash

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You are right, my FC is definitely very high. I have a SWG generator and right now the pump runs 24x7. The pool store showed it was 11ppm
Unless your FC is astronomically high, I doubt that's an issue. Plus, we only care what you show as an accurate FC level with your TF-100, never the pool store. You can always post that FC later, but it's probably not related to what you are experiencing with the TA and CH.

Don't forget to look at the questions in post #10 as those could be pertinent, and also update your signature now that you commented about having an SWG. Your signature is a very valuable piece of info as everyone tries to help.

We'll continue to gather a bit more data before looking to see if your issue should be up-channeled to the TFtestkit.net folks.
 

duraleigh

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The FC level has nothing to do with the TA test (or the CH test for that matter).........using pool water or standard solution.
 

ea3421

Member
Jun 14, 2020
10
Woodmere, NY
Ok, I just measured the TA again on the standard solution. Used the damp rag, the R-0009 drips much better. TA came back at 110ppm for the standard solution (should be 100ppm according to the label) and 110ppm for my pool. Much better!

Just curious - how red should the water turn? It looks more purple/pink? Should I keep adding drops until it's bright red? Or is the first turn to light purple/pink enough?

Let me try CH now, again, on both the standard solution and my pool.
 

duraleigh

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Actually, the end point of ALL these tests (including the CH) is when the last drop you add results in no FURTHER COLOR CHANGE. I was gonna get to that after the TA test was resolved......when are you saying the CH test has ended?
 

CraigChing

Well-known member
Jun 15, 2019
67
Plymouth, Minnesota
Ok, a question then. R-007 is thiosulfate, right? Isn’t that used to remove chlorine for the TA test? I had very high levels of chlorine just after opening this year (> 25 ppm FC) because the pool company opening dumped in a bunch of liquid chlorine. My TA test was way off, I don’t even think I could get it to turn color. After looking into it, I found somewhere that you can double the drops of thiosulfate and then I got good numbers. I compared it to a poolmaster 5 way kit I had and they matched. Am I wrong about that then? Of course I only suggested this for the pool water sample, not the standard solution.