How long do Standard Solutions remain effective? (regarding R-7065 CYA 50ppm Solution Shelf Life)

Stoopalini

Gold Supporter
Jun 8, 2020
590
Central Texas
Pool Size
14060
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
I ordered a set of standard solutions from tftestkits on Aug 17th, and just today got around to trying out the 50ppm CYA solution, to make sure I'm testing my new pool accurately.

I dissolved enough CYA granules in my pool to achieve 20ppm (38oz for my 14,060 gal pool), and when I test the pool water, the dot disapears right at the 20ppm mark.

But when I test the standard solution, the dot isn't disappearing until I get above the 30 mark. I'm mixing 15ml of the standard R-7065 solution (or pool water) with 15ml of the R-13 Reagent solution. Mixing gently by rocking the bottle back and forth for 30 seconds, then pouring into the view tube while holding it waist high and sun to back.

Here are pictures of the 15ml/15ml mix, with the tube filled to the 50ppm mark. I've tried sun to back, sun to side, standing under patio shade, as well as standing under tree shade. In all cases, the dot is pretty visible with the 50ppm standard solution.

So I wondered if this is just what I should be looking for in my pool water test, and I'm actually well above 20ppm (don't know how though, since I used PoolMath to calculate how much to add), or if maybe the standard solution just has a short shelf life and I missed the window.

I searched TFP and found similar posts about this same issue, but never really saw any resolution other than folks giving up on the standard solution.

In this first picture, the dot is actually much more visible to the eye than it appears to the camera (probably due to iPhone camera functionality):

1598721940521.png

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I've never used the 50 ppm testing solution but always thought you would just pour it into the view tube. Mixing it with pool water doesn't sound right as everyone's water would be different.

Edit - looks like I misread your post. Am I correct that you mixed the standard solution with the R-13 & that's per instructions?
 
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Edit - looks like I misread your post. Am I correct that you mixed the standard solution with the R-13 & that's per instructions?

Correct. You use the standard solution as the pool water, and it comes seeded with 50ppm of CYA. So you add 15ml of the standard solution (in place of your pool water), then add 15ml of R-13 reagent, to perform the test.
 
Can't offer anything as I've never used the standard. Just following in case I can learn something.

Because I want to take that lousy, no-good-for-nuttin', frustration-inducin', eyeball-strainin' little black dot out behind the shed and wring its scrawny little neck until it begs for mercy, then give it none! That is, if it had a neck. I HATE the CYA test!!!
:hammer:

Hmm, maybe I should try the standard!!
 
Can't offer anything as I've never used the standard. Just following in case I can learn something.

Because I want to take that lousy, no-good-for-nuttin', frustration-inducin', eyeball-strainin' little black dot out behind the shed and wring its scrawny little neck until it begs for mercy, then give it none! That is, if it had a neck. I HATE the CYA test!!!
:hammer:

Hmm, maybe I should try the standard!!

LOL ... I was actually hoping this was one test I could do without another family member assisting me! Matching colors, and seeing pink change to clear, or red change to purple and then blue ... is quite the challenge for me since I'm colorblind ...

I wonder if there's an electronic color analyzer which can be used at home for the colors? If so, probably unreasonable for the cost though ...
 
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Others here have gone round'n'round about color analyzers and probes and lots of other alternate testing equipment. Several are working on electronic and automatic solutions as we speak. You can search the forum to see if you can find something you can use. Or...

Testing is actually pretty easy. I think a 10-year-old could do it. Certainly a teenager or spouse. If any of them swim, teach them (1) how to test and record results, and (2) that they need to contribute to the household and pool, and this is a good way to do it. My seven-year-old grandson drives his father's truck on their ranch while dad throws the feed out the back. They're way more capable than they're going to let on!
 
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Others here have gone round'n'round about color analyzers and probes and lots of other alternate testing equipment. Several are working on electronic and automatic solutions as we speak. You can search the forum to see if you can find something you can use. Or...

Testing is actually pretty easy. I think a 10-year-old could do it. Certainly a teenager or spouse. If any of them swim, teach them (1) how to test and record results, and (2) that they need to contribute to the household and pool, and this is a good way to do it. My seven-year-old grandson drives his father's truck on their ranch while dad throws the feed out the back. They're way more capable than they're going to let on!

absolutely! I’ve already told my 11 y/o son (12 in Dec) he’ll be responsible for cleaning skimmers, and my 13 y/o daughter (14 in Nov) that she’ll be vacuuming and brushing.

Both have been helping with testing, and are learning. That said, it is still frustrating that I can’t do these tests unless they’re around though. Especially during this initial stabilization period, where I’m testing many times a day to get an understanding of how my pool is going to behave.

Once we get to the stage where testing will be twice a week or so, it’ll be much easier to set a schedule and have it be part of their weekly chores.
 
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One thing regarding the mixing. I don't know if it really matters, but the official instructions differ from what you described. Here from the website:

"1. Fill the red-capped CYA mixing bottle to the bottom of the label with pool water. Now, fill the bottle to the top of the label with R-0013. Mix, then wait at least 30 seconds. Shake once more.
2. Next, get the clear tube marked “CYA VIEW TUBE” and, holding it at waist level, (so you can look down into the tube) slowly fill the view tube with the solution you have mixed. Keep filling until the black dot in the bottom of the tube is completely obscured. Bring the tube back to eye level and note fill level of the view tube. The gradation closest to the fill level indicates your CYA reading. Record it. "
 
One thing regarding the mixing. I don't know if it really matters, but the official instructions differ from what you described. Here from the website:

"1. Fill the red-capped CYA mixing bottle to the bottom of the label with pool water. Now, fill the bottle to the top of the label with R-0013. Mix, then wait at least 30 seconds. Shake once more.

ya, that’s how I was initially doing it, and when I searched the forum, I found posts where this was deemed incorrect, and the the TF-100 instructions really should be changed.

Either way though, I get the same results 😔
 
As in all things pool advice, test results and how they are to be used are guidelines. Every pool is different, as is every owner. Consistent test procedures are more important than precise numbers. If you determine that the way you test gets number X for a result, and dosing based on that number is working in your pool, then your test method is sound. Fox example, if you test CYA and you get 30, and you dose FC based on 30, but FC isn't holding as it should, then you dose to 40. It doesn't really matter if it is actually 30 or 40: you know that when you dose for what you think is 30, your pool is not happy, but when you dose for what you think is 40, your pool is. As long as you are consistent with how you test, so that your results are repeatable, then the dosing you apply to your pool will be correct each time.

Where the true number matters is when you're checking results and/or trying to figure out a problem here, so you do want to be reasonably accurate. But the ultimate judge of your testing methods is your pool.

I don't test CYA exactly as described here, but I dose based on my own MO of CYA testing, and my pool is happy, FC holds fine. :paddle:

A month ago I let my FC drop too low and got a tinge of algae. FC 2.5. It doesn't matter if it was actually 2.5, or 2 or 3, it matters that I can consistently repeat how I tested for 2.5. So if I always use the exact same procedure, and ever see 2.5 again, I'll know I gotta go dose the pool quick. Eventually you go through the same learning curve for each of the tests.
 
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I get that we shouldn’t be crazily obsessed about concrete numbers, but let’s look at this conundrum:

1) TFTestKits sells a standard 50ppm CYA solution (from Taylor, no less).
2) A bunch of us get the dot to disappear with this solution not at 50ppm, but 30ppm.
3) That either means every single one of us is not reading the test correctly (not terribly likely), and we should all add 20 points to our readings, or the standard isn't always as advertised.

Either way, it appears a significant number of people are reading lower than expected levels. I'm ordering an R-0013 and R-7065 from Taylor direct, and we'll see if anything changes....
 
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Yes, do report back if you can show that the TFTestKits standard is giving different results than Taylor's.
@goody222 already did this, and confirmed that Taylor's standard solution tested different than TFP's standard solution.

You can read about his experience here: What am I doing wrong? (CYA)
 
Skimmed it. Did anyone report this back to TFTestKits? What a mess. I've never used a standard. I've "standardized" the way I test CYA, indoors under controlled lighting, and using the same CYA test solution over time, because I bought a large bottle of it. Sorry to keep harping on the lighting thing. But this notion of testing CYA outdoors has never made sense to me and never will (back to sun, front to sun, in the shade, cloudy day, hold by stomach, stand on one leg, rub hand on head... yikes). I decided for myself what 70 looks like, and dose according to that. That and my SWG holds my FC, and so, for me, my CYA testing is sound. As I mentioned, I don't care if it's actually 70 or 60 or 80. I know what my dot is supposed to look like for the level of CYA that works in my pool. Not any kind of TFP doctrine there, just to clarify, just "the rules according to Dirk's pool." YMMV.
 
I get that we shouldn’t be crazily obsessed about concrete numbers, but let’s look at this conundrum:

1) TFTestKits sells a standard 50ppm CYA solution (from Taylor, no less).
2) A bunch of us get the dot to disappear with this solution not at 50ppm, but 30ppm.
3) That either means every single one of us is not reading the test correctly (not terribly likely), and we should all add 20 points to our readings, or the standard isn't always as advertised.

Either way, it appears a significant number of people are reading lower than expected levels. I'm ordering an R-0013 and R-7065 from Taylor direct, and we'll see if anything changes....

I just want to second what you are saying. I recently purchased the Standard Solutions kit and performed the CYA test with the solution (as pool water) about half a dozen times. Like you, I came away with the exact same results every time. I could clearly see the dot at 50ppm. I even took pictures and sent them to TFTestKits describing exactly how I performed the test and asking if my results were accurate (which they stated they were). I realize pictures can be deceiving but these pictures are a very accurate representation of what it looked like visually in the moment. If anything, the dot appeared slightly more visible than it does in the pictures. I'm really interested in hearing your results from the R-7065.

CYA test.jpgCYA test 1.jpg
 
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I just want to second what you are saying. I recently purchased the Standard Solutions kit and performed the CYA test with the solution (as pool water) about half a dozen times. Like you, I came away with the exact same results every time. I could clearly see the dot at 50ppm. I even took pictures and sent them to TFTestKits describing exactly how I performed the test and asking if my results were accurate (which they stated they were).

Thanks for the second, Rip! But wait a minute: TFTestKits admitted your results were accurate? So then what was their explanation about the non-"50 ppm-ishness" of the "50 ppm standard"?
 
Thanks for the second, Rip! But wait a minute: TFTestKits admitted your results were accurate? So then what was their explanation about the non-"50 ppm-ishness" of the "50 ppm standard"?

Let me clarify........ I sent an email to them with the above pictures explaining exactly how I performed the test and asked the question, "does this look correct?" Their reply was "Yes, it does. Remember that CYA is measured in a range, so eg, 40-60 ppm CYA is ok. Just be sure not to get it over 100 or I'd say less than 30. Good job"

I was confused because everything I read and the pictures I saw (e.g. from Taylor's website, link below) showed the dot disappearing much more than what I was seeing with the 50ppm Standard Solution. After receiving their reply to my email, I interpreted the response to mean the dot shouldn't fully disappear and I was recording my own results too low. I was seeing the dot disappear with my own pool water at 30 (about the same as the Standard Sampler) so I basically split the difference and recorded it as 40. I performed a SLAM based on these levels and was obviously in the ball park because my pool water now looks amazing. Maybe the takeaway is to always err on the high side and it will work out. Not sure if there is any downside other than the cost of extra chlorine?

While I totally understand there is a range (and what seems to be a large margin of error), I would like clarification on the Standard Sample I received from them. It does seem like it is inaccurate by ~10-20ppm. However, I am new to all of this so I don't want to point any fingers with my limited experience. My experience dealing with them has been great otherwise.

 
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Oh good, you already found that Taylor page with the three pics. That's what I use for a guide. Done when that dot is "just on the edge of your imagination." In your pics, that test is not done. That seems pretty obvious to me. I also used those images to inspire my testing MO. It looks very much to me like those images were taken indoors (perhaps a studio), with a soft, diffused ambient light (notice, no hard shadows). So it is under those conditions I test CYA. I figure Taylor aught to know how to use their own CYA test, right?
 
Regarding your pics, you've got your back to the sun, so you're kinda creating the diffused ambient lighting. Which is good. But you're looking down at your feet and your background is the tan deck and your stark shadow, creating a scene that is none-to-kind to your eyes/brain, straining to focus on the dot. Notice in the Taylor pics the background surface is a neutral color (white or very light grey) and even (no stark shadows or high-contrast elements) which is much more conducive to observing the dot correctly, and when it disappears.

If in six months you stand in the same place but it's cloudy out, and there's no shadow of you, then you're going to observe that dot in a slightly different way. Especially if you're just glancing at it quickly, which I believe is the standard instruction here for CYA testing. Not such that it matters all that much to the CYA number you come away with, but that is not the definition of a consistent, repeatable testing procedure.
 
Ok, here's what I get with all the permutations:

Using R-0813 reagent from TFTestKits:
------------ (tubes: TFTK (>20), Taylor (>30), Slide)
R-7065 Std from TFTestKits: <20, <30, 30
R-7065 Std from Taylor: 30, 40, 50
(My pool water: 70, 80, 90)

Using R-0813 reagent from Taylor:
------------ (tubes: TFTK (>20), Taylor (>30), Slide)
R-7065 Std from TFTestKits: 20, 30, 40
R-7065 Std from Taylor: 40, 50, 60
(My pool water: 80, 90, 100)

Conclusions: It appears the most accurate value comes from using the Taylor-direct standard and reagent with the Taylor 30-100 tubes, exclusively. For whatever reason, the standards I received from TFTK (and I have two of them shipped to me several months apart) give lower numbers than the former, more so if you use the TFTK reagent and/or the TFTK (20-100) tube. (Curiously, using the sliding tube from Taylor yields higher corresponding CYA levels.)

Just to be clear: I'm not indicting TFTKits by any means; I'm just reporting the results. In fact, a while ago, the difference between the tubes, at least, was brought up, with a review apparently underway, but whose results I can't find; the thread just ends:


Anyway, until I test otherwise in the future with new reagents and standards, I feel obligated to use the following combination: Taylor-direct R-0871 for testing, with the Taylor-direct R-0813 as a standard check, both with the Taylor tubes: either the one attached to the pH comparator (9058) or the 30-100 tube (9197). That triumvirate seems to carry the most accurate results.

I hasten to add that I have absolutely no idea why the other combinations give different results; for all I know, it could be me!
 
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