Need Help!

[wxwmn02]

Do I want an combined chlorine when I do my test?

[CarlD]

Do I want an combined chlorine when I do my test?

No, Zero CC is the best number. But you want to KNOW the CC when you test the water. You either need to test for it or for total chlorine since:

TC = FC +CC

So, if you know FC, then, if you have TC, you can compute CC.