High CC levels with acceptable FC, why?

[Ciaschin]

Hi. I’ve tried to figure this out looking at old threads, but I’m still unclear. I had my water tested today at the store (I do trust it, they always match my home results-I take it there because I find the CYA test in the Taylor kit to be tough to do). Tons of rain, no sun recently, had to drain the pool a couple times recently. Nobody’s been swimming. Pool is clear and debris free. I never usually have any CC, but I had it today. I see no reason why I’d have CC. Nothing gross in the pool. High enough FC to clear any badness and clear chloramines, given my not too high CYA level. I retested it with my taylor kit and confirmed the FC and PH, but found no evidence of CC, though I’m not sure I can detect it at .77 ppm. Zero pink color when adding reagent 3. Any thoughts?

32,000 gallons
SWG
FC 9.92
TC 10.69
CC .77
PH 7.9
TA 87
CYA 60
Phosphates 2649

thanks

mike

 

[Donldson]

I had my water tested today at the store (I do trust it

We don't. Run your own tests and post those results.

 

[Ciaschin]

Ok. With the Taylor kit I got FC of 11.5. And no detectable CC (no pink seen after adding 5 drops of R-0003.) PH 7.9. I did not test everything else. I guess I’d ask if it’s possible to detect a CC of .77 with this kit (k-2006). If so, and I detected none, maybe I don’t have an issue with CC after all.

 

[Newdude]

though I’m not sure I can detect it at .77 ppm

No Worries Cias. They can't detect it either, they just put arbitrary #s to make each test seem that much more accurate. It's total baloney. You didn't list their CH test but I bet you a paycheck it was a specific # like it mattered closer than 25s .... say...... a 392. The same goes for the extra hundredth digit on the FC. It's not right. But even if it was, who would benefit in ANY capacity from knowing they had that extra .02 FC ?

Trust your own test. The reliable test says you are fine. The test that is designed to convince you to spend big on marked up chems has you worried. There will be nothing free about their free test now that they have you worried. And whatever they sell you will start the roller coaster.

 

[Donldson]

maybe I don’t have an issue with CC after all.

Nope. Only issue is an unearned trust in pool store testing.

Anyway I'm glad it is nothing, hope you have a nice evening, and hope this might give you an idea why we really don't suggest letting the store test your water.

 

[JamesW]

FC 9.92
TC 10.69
CC .77

These numbers are complete nonsense designed to terrorize you into buying a couple of hundred dollars worth of secret potion super duper top secret proprietary ingredient do it all potions with goofy names like "Pool Juice 911".

 

[Newdude]

I prefer PoolRx. It went to med school, dontyaknow.

 

[JamesW]

What it's like visiting the pool store.

 

[jseyfert3]

I guess I’d ask if it’s possible to detect a CC of .77 with this kit (k-2006). If so, and I detected none, maybe I don’t have an issue with CC after all.

It is and it isn’t. The test has a resolution of 0.5 ppm per drop when using a 10 mL sample and 0.2 mL per drop when using a 25 mL sample. So a reading of 0.77 isn’t possible but 0.5 or 1 is. There is also an accuracy of +/- 1 drop, or 10% if more than ten drops of reagent is used. Also if for some reason you keep adding drops to the FC after it turns clear those will “cover up” a CC reading in the second half of the test. And finally if your reagent #3 has gone yellow it’s bad and the CC test will be off. This happened to me but I can’t remember if I was measuring more or less CC than I should have been measuring.

If you really wanted to, you could do the 25 mL sample and get more resolution on the test to double check your CC in more detail. But that’s a lot of drops, and time skews the results, so at a FC of 11 be sure to use a SpeedStir and don’t dawdle. However this really isn’t needed, I regularly measure 0.5 ppm CC on my hot tub, and none of the pool (using the typical 10 mL sample size).

 

[Ciaschin]

Thanks everyone! Last ? Does anyone have a test for CYA other than the Taylor black dot at the bottom test?

 

[jseyfert3]

Thanks everyone! Last ? Does anyone have a test for CYA other than the Taylor black dot at the bottom test?

Unfortunately not. My understanding is even the store digital readers are doing the same test, only using light and seeing how much gets through (and often with much worse accuracy that the human version).

 

[Msch99]

A couple of things that will help on cya test.
1). Re read instruction, sun behind back is important, don’t ignore like I did at first…sigh.
2). I hold at eye level, add to 100 mark, then lower and look for dot, if see it, raise up fill to 90etc, etc. until you can’t see dot with quick glance. Don’t stare at it or eyes play tricks on you! You can start at a lower number once you comfortable level is around say 40 somewhere.
3) order test sample from TFTESTKITS. It is 50 I think so you can calibrate yourself.
4). You can dump sample back in mixing bottle and perform multiple tests take an average if you wish or need.