Is there ever TOO MUCH Total Chlorine

Mar 16, 2015
6
Raeford, NC
I found cal-hypo 67% on sale at Lowe's for $75/50 lbs. I'm using it to open my pool. I put in 12lbs and the total chlorine shot to 34ppm, and FC stayed at 0. I'm currently waiting on my -100 kit to arrive. What I have now for readings via our Haz-Mat test kit is.
TC - 24
FC - 0
CYA - 33
TA - 120
PH - 7.6
CH - 165

Really, my question is, can there be too much total chlorine while attempting to gain a FC reading of shock value 16ppm. My pool is a 24' round AG with 12,500 +- 125 gal depending on rain.
 
I didn't see a specific area where TC=FC+CC. But I also didn't see anything particularly addressing if and when there was too much TC without seeing a rise in FC. Do I keep going with hourly additions of cal-hypo until I get to a FC of 16? I'm new to the TFP way of life, but also don't want to bleach my liner or do irreparable harm/damage to any equipment or my pool itself. So I'm guessing that since I don't see anything addressed specifically addressing it being too high, I should just continue to add add add until I see the FC rise?
 
It's ordered and set to be here by end of week. I used a kit from work that's used for Haz-Mat. It's extrememly sensitive and accurate. As well as other parts were tested by a neighbor at the public works dept. only thing I don't have access to is the CC.
 
Seeing as the cal-hypo was extremely cheap, I bought 100lbs. So I guess to waste what's already been put in and not keep pressing until I can gain FC isn't that big of a deal. I will wait for my -100 kit to arrive. But still, is there ever a level of TC that would be considered too high? I live next to a sod farm and had nitrates that were elevated last year. That was eliminated through oxidation and dilution. But my real question is, is there a level of TC where if you still didn't achieve FC, you would stop and look for another route?

Nitrogen, not nitrates
 
We do not care about TC. We care about FC and CC. If the FC is too high, then yes you will damage the pool and equipment. I think high CC can do the same ... BUT ... it is nearly impossible to have a CC that high. Thus, I don't trust your results.

BTW, if you use all 100 pounds of the cal-hypo ... you will add nearly 450ppm of CH to your pool which could put you in danger of developing calcium scaling.
 
First, ignore nitrates. Once you get the proper FC ratio to your CYA/Stabilizer you will be good.


Understand, that the CalHypo is raising your CH which is another bad thing if it gets too high.

How much Pool School have you read? While you wait for your kit start with these:

ABCs of Water Chemistry
Recommended Pool Chemicals

How to Chlorinate Your Pool



It would help us if you would add the following information to your signature


  • The size of your pool in gallons
  • If your pool is an AG (above ground) or IG (in ground)
  • If it's IG, tell us if it's vinyl, plaster/pebble, or fiberglass
  • The type of filter you have (sand, DE, cartridge) and, if you know, the brand and model of the filter.
  • If you know, please tell us the brand and model of the pump, and mention if is it a two speed or variable speed pump.
  • Date of pool build/install, particularly important if less then a year old.
  • What kind/model of water test kit you are using
  • Other significant accessories or options, such as a spa , SWG, or cleaner

So, welcome to TFP!!
 
TC
Total Chlorine

TC is the total amount of both FC and CC in your pool, FC + CC = TC if your test kit uses FAS-DPD to test chlorine, TC - FC = CC if your test kit uses DPD to test chlorine.

Pool School
Handy Reference
Definitions and Abbreviations
 
If your test results are correct, your CC level is 24, which is bad and probably is a symptom of a fairly major ammonia problem.

TC is only used by certain test kits as an intermediate to help you figure out the CC level. We don't speak of TC levels being good or bad, we only talk about FC and CC. With your test kit you can calculate CC = TC-FC. A very high CC level is bad, and also rather unusual. Hopefully your test result is wrong, because it is going to be quite a major project to clean up that pool if your test result is correct.
 

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Still haven't received my -100 test kit. I went with my original calculations and poolcalc, added 4 gals of liquid bleach as cal-hypo WAS raising my CH. 4 gals (121oz) bottles at 8.25% achieved "breakthrough"!!!! I have began the task of ensuring shock levels of FC. Hopefully my test kit comes tomorrow so I can post proper numbers. I owe a lot to this site as my pool store said I needed approx $150 of non chlorine shock to oxidize my chlorine as the pool was in chlorine lock. He said nothing of being able to achieve breakthrough. I am still rereading pool school, as on my work computer the index wasn't available and showing it was blocked like an advertisement, so I didn't know there was so much more to read.
 
Welcome,

Chlorine lock is a myth. If you've used non chlorine shock you will be showing high CC levels.

Let's wait until you have a good FC number when you get your kit.

While TC tells a story, we care about FC first, and then CC, but looking at them on their own gives the entire picture. If you just know the TC without knowing how much of it is Free Chlorine, it does no good. Free Chlorine is what does the work. CC is showing you Chlorine that's been used up already. You could have a high amount of CC in a given sample but have nothing more than used up Chlorine. This is why FC is so important to know.
 
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