R-0007 - what is it an why

[Billtkat]

I noticed the Alkalinity teat kit has an extra step to test alkalinity - 2 drops of R-0007. Why and what is it ? The HTH kit i purchased a couple months back , before I knew about and now have my TF100 only has 2 steps . 5 drops of indicator and drop by drop of the titrant.
Because I new using the TF100 and some results could be based on me doing something wrong I do use both to compare as a guide to see if I am OK in my testing. All test are coming out the same except this one - When I use the HTH , 2 step I get a result of 100. When I use the TF100 with the 3 steps I get 140 - Got to be me or the R-0007 , 2 drops I add does something that creates the variance -

 

[mknauss]

R0007 is a chlorine neutralizer. Thiosulfate.

 

[Donldson]

It's a chlorine neutralizer. Chlorine can bleach out the R-0008 so Taylor includes the neutralizer to prevent this from happening.

Are you wiping the R-0009 tip while doing the test? Because TFTestkits gets such new product from Taylor the bottles sometimes carry a static charge which can cause the drops to jump away from the bottle before they are fully formed, causing a falsely high result. Wiping the bottle between drops can help that. This static charge will go away over time, it is just due to the extremely new product.

 

[ajw22]

R-0007 is sodium thiosulfate which neutralizes chlorine which can interfere with the TA test endpoint. Chlorine can cause the endpoint to be yellow or clear rather then pink.

 

[Billtkat]

Thanks so the

It's a chlorine neutralizer. Chlorine can bleach out the R-0008 so Taylor includes the neutralizer to prevent this from happening.

Are you wiping the R-0009 tip while doing the test? Because TFTestkits gets such new product from Taylor the bottles sometimes carry a static charge which can cause the drops to jump away from the bottle before they are fully formed, causing a falsely high result. Wiping the bottle between drops can help that. This static charge will go away over time, it is just due to the extremely new product.

I will try that as the drops were coming out but not like a good well formed drop as in other test if that makes sense - Maybe that is the issue as the results were way off between the two - I am hoping it is user error

 

[Billtkat]

R-0007 is sodium thiosulfate which neutralizes chlorine which can interfere with the TA test endpoint. Chlorine can cause the endpoint to be yellow or clear rather then pink.

So the HTH kit allows the chlorine, which I know I have (FC of 3.5) to stay and drives the results lower ?

 

[ajw22]

So the HTH kit allows the chlorine, which I know I have (FC of 3.5) to stay and drives the results lower ?

It messes with you seeing the precise color change. You see a color change before you should with the chlorine bleaching out some of the color. Thus a low reading.

 

[Donldson]

No, the HTH just cuts cost by not including this step. The presence of chlorine does not affect the results, but it could affect the color of the test at higher chlorine levels (such as during a SLAM). If the colors get bleached out the test is still accurate because the change in color still happens, but it is more difficult to tell when that change happens. This can happen with the Taylor too, but at chlorine levels well in excess of anything we would ever recommend.

 

[Billtkat]

OK , wiping the tip did help for sure. I used my speed stir to mix between purposeful drops. At 10 the first sign of red / pink (with the light on it looks pink to me) shows then flips back into green - At 11 drops the water is clear to light pink with light on while spinning , then at 12 it is red. I assume the full red or dark pink is the 120 i would record , correct ?
BTW - that little spinning thing was well worth the purchase ! I use it on everything it calls for mixing except CYA and the Chlorine test with the powder -

 

[Donldson]

Yep, when any further drops would result in no color change. 120 it is.

 

[Yorker]

oops found my answer