CH confusion

[ateam]

I got my TF-100 a couple days ago and I'm a little confused by the CH test.

Can someone tell me definitively when it ends?

I have the speedstir and I count out 10 drops of R-0012 and see blue. I think it's over and my reading is 200 CH.

If I let the speedstir keep going about 30 seconds later it turns back to pink. One more drop and back to blue. wait 30 seconds, back to pink, one more drop, back to blue. And the process repeats for several more drops. Over the past couple days I've gotten CH readings anywhere from 200 to 425 and I'm not sure what to believe.

Do I keep going until it never turns back to pink, or am I done with that first color change at 10 drops?

Thanks for the help.

 

[ateam]

I have the speedstir and I count out 10 drops of R-0012 and see blue. I think it's over and my reading is 200 CH.

oops - 25 * 10 = 250, not 200.

 

[pooldv]

All tests end when the first change occurs and the next drop makes no change. None requires a waiting period after the color change to see if it changes back. I think several of them wil change back if you wait.

Here are some handy videos that show the test kit in action.
https://www.youtube.com/user/tf100testkit?feature=results_main

 

[JRHurst00l]

Also, take a look at the extended test directions for CH (Extended Test Kit Directions). It talks about the "fading" end point and how to remedy it.

 

[Richard320]

I'd go with the higher number.

Since I regularly test CH in the 800+ zone, I consider myself an expert on this test.

Often when I'm stalled at the maroon stage, an extra cycle of the speedstir will push it to blue. But sometimes it pushes it back to pink. When it turns blue and stays blue, that's when it's over. I've never seen that test change back after sitting awhile, the way the FAS-DPD test does.

 

[pooldv]

I definitely defer to Richard on high CH testing and water management.

 

[ateam]

Thanks Richard. That is exactly what I needed.