Cya testing and reading.. Your thoughts please

[nabril15]

Good morning
I did a cya test this morning using this recommended method, with the sun on my back:
1. Fill the thin cylinder to 100 and look down into it.
2. Look away and fill to 90 and look down at it.
Etc, etc until the dot is out of sight. Of course, this is the difficult and subjective step.
The picture below is at 50.
View attachment 88256

This is 60
View attachment 88257

Would you say that my cca is 60 or 50? I lean towards 60.

 

[Texas Splash]

My eyes like 60.

 

[Dirk]

See pics at the bottom of this page (from the manufacturer of the test):

Why Monitor Cyanuric Acid?

Your CYA is 60.

I fudge/round up. If I use a CYA number that is slightly higher than it actually is, that means I'll be adding a little bit more chlorine than is needed. While, technically, extra chlorine will burn off in the sun a bit faster, which is slightly less cost effective, it won't do any harm to you or your pool.

If I fudge/round down, and thereby use less chlorine than I should be, I run the risk of getting too close to, or below, the minimum recommended amount of chlorine for my pool, which could mean an algae outbreak or somewhat less safe water for my family.

Better safe...

 

[nabril15]

See pics at the bottom of this page (from the manufacturer of the test):

Why Monitor Cyanuric Acid?

Your CYA is 60.

I fudge/round up. If I use a CYA number that is slightly higher than it actually is, that means I'll be adding a little bit more chlorine than is needed. While, technically, extra chlorine will burn off in the sun a bit faster, which is slightly less cost effective, it won't do any harm to you or your pool.

If I fudge/round down, and thereby use less chlorine than I should be, I run the risk of getting too close to, or below, the minimum recommended amount of chlorine for my pool, which could mean an algae outbreak or somewhat less safe water for my family.

Better safe...

Thanks Dirk for that link and comments. It is very helpful
The label in my TF-100 test bottle was placed slightly askew (or tilted) - a degree or 2. So, every time that I fill that bottle I wonder how much pool water and reagent to add. Do I fill to the lowest end of the label or the higher end?? Etc. Like i said, the label was not applied at a perfect 90 degree angle; perhaps, it's not that big of a deal.

 

[Dirk]

I have a different kit, and bottle, so I'm not quite sure what you're describing. The ratio of reagent (R-0013) to pool water is 1:1, equal parts, if that helps. The total amount you end up with is not critical, as long as you have enough to hide the dot.

Here's how you could "calibrate" your bottle. Fill to the lower mark, pour that into something else. Fill to the lower mark again, then pour the first amount back in. You should now be at the upper mark (twice as much as the lower mark, or 1:1 ratio).

 

[nabril15]

I have a different kit, and bottle, so I'm not quite sure what you're describing. The ratio of reagent (R-0013) to pool water is 1:1, equal parts, if that helps. The total amount you end up with is not critical, as long as you have enough to hide the dot.

Here's how you could "calibrate" your bottle. Fill to the lower mark, pour that into something else. Fill to the lower mark again, then pour the first amount back in. You should now be at the upper mark (twice as much as the lower mark, or 1:1 ratio).

Dirk, I understand what you mean. Here is the label I'm referring to :
View attachment 88258

It's hard to tell inna picture, but that label is slightly off angle. But I get your point of 1 to 1

 

[Kuhbander]

My label is sewed on my bottle as well. When I do the CYA test, I weight the liquids on a digital food scale. 15ml of pool water and 15ml of R-0013. It takes 3 or 4 drops to equal a ml so when I get to 13 or so I do 1 drop at a time until it hits 15.

 

[Dirk]

It's hard to tell inna picture, but that label is slightly off angle. But I get your point of 1 to 1

Huh, it doesn't even look half way up from the bottom.

My bottle only has 14ml total, so I use 7ml of reagent, and 7ml of pool water, and that is enough to fill my testing tube. That's the kit from Taylor, not the TF-100.

If you have doubts about the label, find a reliable way to add the proper amount of reagent and pool water, and then mark the bottle for each, for the next time.

Or, they're only 3 bucks, if 14ml is enough for your test tube:

Bottle, Calibrated (7 14 mL), .75 oz w/ dispenser cap, plastic (for CYA)

 

[duraleigh]

as always, TFTestkits will send you a new bottle tomorrow if you call them and ask for one. It will make no difference on your testing at all but if it's bugging you, you should ask for another.

 

[kimkats]

as always, TFTestkits will send you a new bottle tomorrow if you call them and ask for one. It will make no difference on your testing at all but if it's bugging you, you should ask for another.

I will tell you TFTestkits is all about customer satisfaction so will do just like Dave says and send you a new one. I will also tell you it really will not make that much of a difference in your test results. That tiny bit does not make much if any difference so long as it is 1 to 1. Do what works best for you.

 

[OTPirate]

Another easy thing to do is use your graduated cylinder-fill up to 15 ml water and 15 ml R-0013 and pour in mixing bottle. So long as it’s a 1:1 ratio.

 

[bo_mull]

I'm confused a little bit here. In the pictures above, I can see the dot in the one labeled 50 but I can't see the dot in the one labeled 60. In my test kit K2006, 50 has more liquid than 60 does, so if you can see the dot at 50 then you should be able to see the dot at 60 also.

 

[pabeader]

I'm confused a little bit here. In the pictures above, I can see the dot in the one labeled 50 but I can't see the dot in the one labeled 60. In my test kit K2006, 50 has more liquid than 60 does, so if you can see the dot at 50 then you should be able to see the dot at 60 also.

I was wondering the same thing. I 'assumed' that they just mislabeled the pics.