Question on CC's

[CurtB]

Hi,
Just have a question about the overnight test. It says you pass when water is clear, FC loss is 1 ppm or less and cc is .5 ppm or lower. My water is very clear, I had no FC loss at all but my cc is 2 ppm. I thought cc is the byproduct of chlorine doing its job. If the FC didn't drop at all then how can their be cc's? Also if the FC didn't drop at all doesn't that mean it didn't "eat " any algae. Why do we care about the cc level? Thanks.

 

[cledee]

Have you used any "Chlorine Free Shock" or "Oxidizer" in your water recently? These will show as CC on the Chlorine Test.

 

[Newdude]

Or did you forget to turn the SWG off ? So it made up your loss overnight giving you a false positive ?

 

[CurtB]

No just regular liquid chlorine and SWG is off.

 

[Newdude]

Is it covered?

 

[CurtB]

Nope, took cover off last week and has been in shock since. It's looking very clear so that's why I'm wondering if I have to worry about the .5 cc or less.

 

[Newdude]

.5 is ok. 2 is not. Which is which ?

 

[CurtB]

It's at 2, I just meant it should be at .5 before you stop shocking. I just don't understand how the cc could be that high if my FC didn't drop at all. Where do the cc's come from then?

 

[Newdude]

@mknauss ?

 

[CrystalRiver]

Did you test CCs the evening before? Rising from 0 to 2, with no corresponding FC loss, would be strange indeed. If they were 2 in the evening, then not dropping overnight is to be expected.

 

[CurtB]

No this was the first time I did the overnight test so the first time I checked CCs. My question is, why do we worry about the CCs being at .5 or less? If they are a byproduct of the chlorine working then who cares? Why do we keep shocking to get the CCs down? Wouldn't adding more chlorine just cause more byproduct? I'm confused. LOL

 

[Donldson]

If they are a byproduct of the chlorine working then who cares?

They are a byproduct of chlorine reacting with ammonia. If you have CC, then the chlorine is reacting with something. That's not a sign to let up, that's a sign to keep going until there's nothing left for the chlorine to react with.

Can't say why you are getting the FC readings you are getting, but it doesn't really matter. If you have CC then you have something in your water that shouldn't be there.

 

[CurtB]

OK, thanks for the explanation.

 

[CrystalRiver]

You can check CCs without doing OCLT. If you have CCs, there's no need to be up before dawn doing OCLT yet.

 

[CurtB]

Good point, thanks