Hello all,
My friend at work believes that all he needs is an OTO tester to check his chlorine. He says that when he puts the five drops in the yellow side, the color you first get is his Free chlorine, and after a few minutes, the color you get is your total chlorine. If there is a big difference, you have combined chlorine, and should shock.

I told him that I did not think that was correct, and that you need a DPD testkit to accurately test FC, CC and TC. Even if he was correct, if your CC is more then .5ppm, it should be addressed, and a person could not even tell a .5ppm color change.

Am I right? I don't understand how someone could spend over $20,000 on an inground pool, $700 on a pool light, but not spend more then $4.00 on a testkit.
I love both my "old" PS232 and now my new PS234 testkit. Thanks Ben!

Frank D.