I'm looking at getting the tf100 kit, among others, but I'm not understanding why it comes with an OTO test and FAS/DPD if so many people say they don't use the OTO. Am I missing something?
I'm in the same boat as swoopman. I think I've used the OTO chlorine test twice. I like to keep my chlorine on the high end of the recommended level of 3-7 ppm (CYA @ 40 ppm, so I usually target 6 ppm FC).
Since the OTO test doesn't read past 5 ppm, it's just easier to use the FAS-DPD test daily.
I will second the recommendation of the SpeedStir. It makes life quite a bit easier and, IMO, makes the testing go faster.
The whole test kit area is overwhelming to me, even after reading pool school 500 times. I thought OTO tested TC not FC. TC on its own isn't much help is it or do you accept that (for the daily testers) until you have cloudy water, chlorine smell, or something like that? Then you break out the FAS/DPD?
There has been some good info above, one nice thing about the OTO test is it makes a nice sanity check if you suspect your reading with the FAS-DPD test is wrong. As to the TC vs FC question, the OTO test can be used to estimate the FC and CC (which make up TC), by looking for a color shift some number of seconds after the initial reading. However if you are looking at economics of these things, the OTO test makes little difference as it is one of the cheapest in the test kit, in fact the whole K-1000 kit with the OTO test, the pH test, comparitor block and case sells for only about $10.
Hmmm...I thought the simple answer was that the oto comes bundled with the pH test in the taylor kit...doesn't mean you need it or have to use it. I use the pH side...never the chlorine side.
Just trying to see the benefit/uses of the OTO. Like I didn't realize that was the same test for pH. It's a little confusing trying to find all the info I'm looking for online because I can't look at the kit in person.