CC check?

[xDom]

To all those that religiously check their FC level and are totally confident that you’ve got at least a 7.5% FC/CYA..
Do you bother checking for combined chlorine?

 

[mgtfp]

Not really.

 

[YippeeSkippy]

Truthfully, I do. It's just a habit as that is how I learned to do the FC/CC testing so it is ingrained in me.

Maddie

 

[xDom]

Truthfully, I do. It's just a habit as that is how I learned to do the FC/CC testing so it is ingrained in me.

Maddie

So how often have you found to have an elevated CC level, with the correct amount of FC?

 

[SumOfOneInteger]

So how often have you found to have an elevated CC level, with the correct amount of FC?

I’m the same as Maddie. I do it out of habit. To answer your question: almost never do I notice even a tinge of pink. I ride the high side of suggested FC levels and dose even hotter when I know I’ll have a heavy bather load just to make sure.

 

[YippeeSkippy]

Well I sometimes do when the autocover hasn't been opened lately. I let the sun and air get to the pool and retest and its all good hours later. i know the elevated level is just retained gases.

 

[SoDel]

If FC drops anything more than maybe 1 or 2 ppm from one day to the next, I would ordinarily check CC. Otherwise, basically never. I also never let FC get anywhere near as low as 7.5% of CYA

 

[xDom]

also never let FC get anywhere near as low as 7.5% of CYA

Ok, what do you run yours at?

 

[SoDel]

Ok, what do you run yours at?

I keep it between 10 & 20%, but closer to above 15% most of the time. I reduce the SWG by a couple/few points as FC reaches 20% or increase it a tad if it heads towards 15%, generally pretty much follows as the hours of daylight change seasonally (i.e., I don’t have to mess with it very often at all). Just makes it a little easier for me — never have to really worry much if an impromptu pool party or some other random something is going to cause a dip between testing. YMMV. Have never had anything other than sparkling crystal clear water (and want to keep it that way without thinking much about it ).

But back to the thread — if FC drops say 2 ppm or more from one day to the next, that’s not usual for my pool so I’d check CC to see if something was going on. Otherwise, I never bother to.

 

[mknauss]

I honestly cannot remember the last time I did the CC test. If the water is clear, the FC normal, and no issues, why?

 

[JoyfulNoise]

CC’s aren’t as much of a problem in a properly chlorinated outdoor pool. The UV-A/B light incident on the pool causes chemical reactions to occur with the chlorine in the water to create some very powerful and short-lived chemical species called radicals (hydroxyl radicals are a common species). Radicals are powerful oxidizers that can destroy even the most persistent CCs. So unless the pool is a green swamp and people aren’t urinating in the pool, the CCs will mostly be below any detectable limit.

 

[JamesW]

I rarely check, but I also know when the CCs “might” be elevated.

If I have reason to suspect CCs, I will check.

Chemistry follows predictable rules, and the better you understand those rules, the better you can manage the chemistry with fewer tests.

However, until you really understand the chemistry, you need to test more often.

If you are always able to predict what any test will be, then you are probably testing enough.

If you are ever surprised by a test result, you are probably not testing enough.

 

[JamesW]

For commercial pools, high use pools or indoor pools, you need to test more often.

Many public pools dictate the testing frequency based on the local codes.

For an outdoor, residential pool with light use, the CCs will rarely be an issue as long as the FC is well maintained.

You might get 0.5 to 1 ppm of CC, but they will usually go away pretty quickly and I would only elevate the FC to about 15% to 25% of the CYA to manage transient CC levels.

 

[mgtfp]

Chemistry follows predictable rules, and the better you understand those rules, the better you can manage the chemistry with fewer tests.

However, until you really understand the chemistry, you need to test more often.

If you are always able to predict what any test will be, then you are probably testing enough.

If you are ever surprised by a test result, you are probably not testing enough.

^^^^^ This to a T

 

[xDom]

I keep it between 10 & 20%, but closer to above 15% most of the time.

So what CYA level are you on?

 

[generessler]

I do it a couple of times a week. We get lots of tree dandruff most of the year. CC is a cue to clean the skimmer and pump baskets. Or if they're already clean, the filter. I've seen it go to .5 in that case. Most of the time I just add the R-0003 reagent and just barely see a pinkish tinge, so stop there, as one more drop of R-0871 is certain to be enough.

 

[SoDel]

So what CYA level are you on?

Right now, about 50. For me at least, the CYA test is the most subjective so maybe it’s more like 60. I don’t think it’s 40. (I have the CYA 50 standard solution and that helps “calibrate” the eyeballs but it still has a subjective component to it). I aim for around 60 but we had a lot of rain with Ophelia, and this late in the season, no reason to bump it back up. But the subjectivity of the CYA test is maybe another reason (or excuse lol) to run FC a little higher than “necessary.” It doesn't cost me really anything in the grand scheme and makes things easier for me.

For the CC test — unless an unusually high bather load with lots of kids (rare) or some frogs die and start decomposing behind the skimmer weir where I don’t notice them for a while around the same time flocks of ducks decide the pool is a great place to do what ducks do, with lots of duck do do (can’t say what it is on this site lol), the FC is stable and if FC is stable, testing for CC isn’t something I do.

 

[newdude]

I believe I saw a single digit FC twice this season. Both times were 9.5 and it was probably user error because I get sloppy after 10 drops when it's still good and pink/red

CCs are not a concern for some people.