HAVE to shock at 1 CC?

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,363
East Texas
Ok, been cloudy and cool here for the past couple days (thank God) in Texas. Checked my water this a.m. Chlorine above minimum for my CYA level as usual. For grins I did the CC test and it came out 1. My buddy and I split a cord of wood yesterday afternoon and plunged into the pool sweat and all! I've searched back several posts that have said CC wll burn off with sunshine and that it is only indicative that the FC has combined with organics. Pool is cystal and clean and clear-all other items are in range. Is it absolutely positively necessary to shock, or just wait for some sunshine to erase that CC? Mostly suny today so I'll check CC level again this evening. Thanks in advance.

woodyp
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
31,713
Sebring, Florida
You will do no harm by shocking your pool. That would be a best, quick path.

That said, I would probably take a somewhat easier route and simply elevate the chlorine above normal by maybe 30-50%...there's no set number that spells success. Anyway, this elevated level (it can be as simple as perhaps a big jug of Clorox.) will speed the process of returning your CC's to less than 1.0.

You could also just leave it alone and it would come down on it's own but that would not be my first choice.
 

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,363
East Texas
Does it in any way mean that the pool is not sanitary enough to swim in? Is there a higher level off CC at which it is NOT sanitary enough? I'd like to see a nice, concise "sticky" on CC in pool school because I think people go into panic mode over it too much. I've kinda thought if you get over .5 CC that you're on the verge of some kinda disaster, if you're not already there!

And thanks duraleigh.
 

dmanb2b

TFP Expert
LifeTime Supporter
Apr 4, 2009
3,734
NY
woodyp said:
Does it in any way mean that the pool is not sanitary enough to swim in? Is there a higher level off CC at which it is NOT sanitary enough? I'd like to see a nice, concise "sticky" on CC in pool school because I think people go into panic mode over it too much. I've kinda thought if you get over .5 CC that you're on the verge of some kinda disaster, if you're not already there!

And thanks duraleigh.

There is clear direction in PS...you should shock with CC above 0.5. Dave is giving you an alternate, which will likely work and the reason he did is because it sounded like you did not want to go through the shock process. Pool school instructs you to shock.

CC at or below 0.5ppm is considered safe "TFP" pool...however there are thousands of pools out there where I am sure folks are swimming around in god knows what level CCs :shock: ...and they live on. :goodjob: It's personal preference.
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
31,713
Sebring, Florida
...and they live on.
.....for the most part :shock: :shock:

Woody brings up a decent point that I think is worth talking about.....the guidelines we use here on TFP. The operative word is "guidelines" they should not be construed to be inviolate.

Now, these guidelines have been developed by some pretty dedicated and smart people (Jasonlion and chem geek, for example) but they have never been intended to mean....

"If you elevate your FC to 18ppm, your pool will be crystal clear but, if you only elevate to 17ppm, the algae will smother your pool and creep into your yard and your wife will leave you!!"

So, as we've said many times here, the key to the pool management we talk about (BBB) is your own knowledge being eventually at a point where you almost have an intuitive "feel" for what's right for your pool and what's not.

That's why we are so negative about all the pool store "magic bullets" they love to sell...we want everyone here to work towards understanding the nature of your pool so you don't ever have to think about needing the stuff in the pool store.

Does it in any way mean that the pool is not sanitary enough to swim in?
No, not really. But it is an indicator that you need to take some action.
 

chem geek

TFP Expert
LifeTime Supporter
Mar 28, 2007
12,082
San Rafael, CA USA
Combined Chlorine (CC) is mostly chlorine combined with urea (probably monochlorourea and dichlorourea) since urea is the largest component of sweat and urine. The second largest component is ammonia so chlorine combined with ammonia, mostly monochloramine, is also registered as CC. So long as you still measure reasonable Free Chlorine (FC), the pool is safe, but much higher CC levels can be smelly and irritating. If your pool doesn't smell bad, then the levels of CC in the pool are probably not irritating. It's an indicator and nothing to panic about.

If the CC isn't dropping fast enough on its own as it should, then shocking will usually speed up the process. Exposure to sunlight also helps a lot, especially for the chlorine combined with urea since that doesn't get oxidized by chlorine very quickly unless the temperatures are hot (i.e. a hot tub) or there is exposure to UV in sunlight. We have the simple rule of shocking when the CC > 0.5 ppm mostly because that indicates some sort of problem such as nascent algae growth or something in the pool not getting dealt with quickly enough.
 

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,363
East Texas
Added 1/2 gallon of extra bleach to my normal dosage--checked this morning-----and CC level is a big fat ZERO. It was not necessary to bring it to and keep it at shock level for a sustained period. Thanks duraleigh. I'm still in the "Shock-Free" club!
 

mynewpool

Well-known member
Mar 17, 2010
1,082
Spring, TX
On another note with guidelines, My FC level for a CYA of 30-40 is an FC of 4-5. I have always kept mine at 6, just to be on the safe side.
 
Thread starter Other Threads of Interest Forum Replies Date
S Spas and Hot Tubs 3
K Swimming Pool Start-up and Closing 1
A Testing and Balancing Your Water 7

Other Threads of Interest