Quote Originally Posted by vanhout
When you do the 25 cc method, do you add more than 5 drops of the R0003? How about for the FC measurement - what does each drop of the R0871 equal in terms of FC?

Thanks!
Sorry, I missed this when you posted it.

I should have noted in my first reply that I use a Taylor K2006 instead of Ben's kit (he was between kits when I needed one but I have purchased replacement reagents from him) The K2006, however, uses many of the same reagents and I think the FC test is identical. So, assuming the FC test is the same between the K2006 and Ben's tests (thoroughly mix two scoops of DPD powder into the water sample and then drop and swirl 0871 until the sample goes clear), yes, you will be able to test to the 0.2 ppm level by using a 25 CL sample instead of a 10 CL. With a 25 CL sample, each drop of 0871 will represent 0.2 ppm FC.

Again though, I'm not sure that there is much practical benefit in doing this routinely (or maybe even ever) and it will make you consume 0871 over twice as fast. It also makes the test more time consuming (more drops and swirls).