CYA testing....Taylor's response.

[Ecoke]

I have been reading much discussion on here regarding the accuracy of the CYA testing. It's definitely a tough one. That being said..I watched the Taylor "How to" video again yesterday on their website. I was surprised that no mention of doing the test outside..sun at back..etc was mentioned as video shows it being done at what looks like inside at a lab table. I grabbed the book out of the K 2006 kit...also no mention of where to do the test...

So I emailed customer support at Taylor and said...Hey..What's up with this??..I mentioned following TFP and the recommendation...

Here is the response...I didn't ask if I could post it...so I will leave the contact's name off...but this is from Taylor Customer support dept.....


"Hi Ed:

Your email was forwarded to me as I handle all the tech calls and emails into Taylor.

The CYA test is a turbidimetric test and, honestly, the lease "accurate" of any of the tests in your kit because everyone will interpret "when the black dot just disappears" differently--regardless of techniques and even using the same sample water! That's why there's no need to be specific when trying to get an answer. You don't need to see if you have 42 ppm CYA in a sample--you just need to make sure it's between 30-50 ppm (the industry-recommended ideal range).

With that all being said, how you do the test is dependent on the user. I've found that doing it outside with the sun on my back and the tube waist high versus "cloudy" days makes no difference. The only recommendation we make is to not face the sun directly (and that's for any test)."

From my limited experience trying to do it...and from you folks who have done what seems like bazillions of tests...IMHO...your recommended method is in fact the best...for me...and I will continue to use it in order to stay as consistent as I can. I have noticed a difference in the values I get when NOT done as you recommend. I'm not trying to stir up any debate...You folks have been amazingly helpful and knowledgeable to me these last few weeks as I get going on the TFP methods. I just was curious in trying to learn more as to why there was no mention of it in their guidelines. I just thought I would share their response.

Thanks,

Ed

 

[BestJoeyEver]

Honestly Ed, I have noticed zero difference doing it in the sun or in artificial light. I have however noticed a difference in how far away I hold the test.

 

[Ecoke]

My issue is probably dependent on my loss of eyesight...seems I need all the light I can get...I'm not old by a long shot..but man...the ole eyes aint what they used to be!

 

[duraleigh]

People will continue to agonize over this test for as long as it is the standard test. The response from Taylor clarifies the reason for this.

Most of us want a CYA result of 32.5 or something as accurate........that's not going to happen.

If you have a manually chlorinated pool, your CYA should be somewhere between 30-50 ppm. (60-80 for swg pool) So when you get a test that returns values anywhere in that range, Don't sweat it.

You'll get better and better with this test the more you practice. Back to the sun, sunny day, etc., etc. just simply seem to make little difference after you have done the test a couple of hundred times.

Even if you get it wrong by 15 points or so, it is not a crisis. Run the test 2-3 times (pouring back and forth, don't use new reagent each time) and then have fun with your family so everybody gets a guess. You'll get it figured out and you don't have to agonize over making this test harder than it needs to be.

We should all probably reread that text in blue above......it has a great deal of truth in it.

 

[spinPHD]

I also think people agonize over it because too high of CYA is what brought them here in first place. After realizing you have too high of CYA and forced to drain, you want to do everything in your power to never get to that point again. Once you feel more comfortable with test and realizing that consistency with the test is more important that accuracy. If you get 50cya, 8 out of 10 times but get 40 the other 2 times, go with the most consistent number.

I think that is why it's good to have a standard for how people perform the test. If you always perform the test the same way you have better chance to get consistent results.

 

[duraleigh]

Well put, Spin, I agree completely.

 

[wakebob38]

I am very disappointed in this test. I just used my Taylor kit for the first time today, and the CYA test is the most important to me, but it is not at all accurate. I would like to know how other SWG pool owners keep it between 70-80 using this test. Mine read 80, but I have no confidence that it isn’t actually 100 and way over. I bought the kit because the pool store testing was often way off from the strips and I thought this would be a color change test like all the other ones.

 

[PoolguyinCT]

I am very disappointed in this test. I just used my Taylor kit for the first time today, and the CYA test is the most important to me, but it is not at all accurate. I would like to know how other SWG pool owners keep it between 70-80 using this test. Mine read 80, but I have no confidence that it isn’t actually 100 and way over. I bought the kit because the pool store testing was often way off from the strips and I thought this would be a color change test like all the other ones.

Practice & consistency..

*i would hope a pro test differs from a test strip.

 

[ping]

I tip that I use is to never stare at the dot, I think it ingrains the image in the brain and it is hard to get rid of. I suggest filling the tube to say 50 and take a quick look to see if you can see the dot. If you can see it, fill the tube to 30 and take another look for the dot. If you can't see the dot, empty the tube and refill with less solution. I'll empty and refill the tube several times to get my reading.

 

[aussieta]

as ping said
i fill to the first graduation
hold tube at waist with back to the sun
and a quick glance 2-3 seconds
then fill to next graduation and repeat
if the numbers didnt match a previous test
i pour the solution back into the squirt bottle and start again
there is a "standard solution" available if you want to practice to find the best light/distance etc

 

[ssrhodes6]

CYA is reading zero, over flowed the tube and could still clearly see the black dot. Error or just need to add stabilizer?

 

[ping]

That would mean the CYA is less than 20 and time to add enough for 20ppm which should be about 5lbs of CYA. Retest after the CYA has dissolved from the sock.

 

[wakebob38]

Thanks! That’s what I will do.
And yes, I wouldn’t expect the strips to match the pool store.

 

[Oly]

What is the temperature of the water you are testing?

 

[jimim]

i was coming here to post something similiar.


So my water is cold right now. 50 degrees. I bring it in the house to let it get up to 65 ish. That ok?

Second. So I really think I'm at 50. I manually chlorinate for now till I finally fire up the salt cell. So I have been using 50 as my targets for FC. What if it's actually not 50 but lower is tht ok to be usign the higher target? I assume it's better to use the higher range and be wrong vs using the lower range and actually being higher cause then you aren't adding enough chlorine.

So this is my question. I know I have to bring my CYA up for the salt cell cause its recommended. What if I don't and just assume it's in the range so I don't overshoot and I'm not keeping the chlorine high enough and then fall below the minimun recommended level of FC?

Does that all make sense?

jim

 

[domct203]

i was coming here to post something similiar.


So my water is cold right now. 50 degrees. I bring it in the house to let it get up to 65 ish. That ok?

Second. So I really think I'm at 50. I manually chlorinate for now till I finally fire up the salt cell. So I have been using 50 as my targets for FC. What if it's actually not 50 but lower is tht ok to be usign the higher target? I assume it's better to use the higher range and be wrong vs using the lower range and actually being higher cause then you aren't adding enough chlorine.

So this is my question. I know I have to bring my CYA up for the salt cell cause its recommended. What if I don't and just assume it's in the range so I don't overshoot and I'm not keeping the chlorine high enough and then fall below the minimun recommended level of FC?

Does that all make sense?

jim

When my water is <60F I will warm it up in the house by putting my sample bottle into container of warm water (like heating a baby bottle before there were microwave ovens). Then I conduct my test outside in the sunlight.

I easily went through an 8oz bottle of CYA reagent my first season with my K2006. After about 3 or 4 weeks of testing daily or every 2 days, I really had a good grip on it. Now I check every 4-6 weeks and I'm very confident with the result.

I also fill to a graduation then look for the dot with a glance. If I still see it, I fill to the next graduation and repeat.

Once I determine the test result, I dump the sample back into the mixing bottle and repeat the test with the same sample. You can do this multiple times with the same sample. I also try to do the test about the same time of day, and I stand in the same general area. This helps with consistent results due to consistent lighting.

 

[jimim]

that's exactly what I do. But I'm not confident in my eyes. sometime I see it and other times I don't. i do the glance thing. i'm just worried i'm going to actually have a higher level than I record and then i'm actually not dosing high enough for my FC. that's why I'm assuming its 50 cause I know for sure it is't 60 but at times i swear it's 40. so i took it as 50 so i don't kee pthe fc too low and something starts to brew.

 

[DeanP66]

If you assume it's higher that it actually is and bump up your FC accordingly, the worst that will happen is that you will go through chlorine a little bit faster because the excess chlorine will burn off at a faster rate. This way is much preferred than underestimating the CYA level and adding too little chlorine at that lower threshold.

 

[basecase]

For those of you stressed or anal-retentive about the accuracy of the results, use statistics. I recommend testing many times (with the same sample). Document the results in a spreadsheet. After you have more than a dozen results, average them. Use a "median" average (Middle value separating the greater and lesser halves of a data set). That is your CYA number.

If you run the test with the same sample enough times, eventually the median levels out (stops changing regardless of the number of tests you keep doing).

You may also want to throw out the lowest and highest values before calculating the median value. The assumption is they are anomalies.

I also wear my glasses because I found the results were quite different without them.

 

[jimim]

If you assume it's higher that it actually is and bump up your FC accordingly, the worst that will happen is that you will go through chlorine a little bit faster because the excess chlorine will burn off at a faster rate. This way is much preferred than underestimating the CYA level and adding too little chlorine at that lower threshold.

ok that was my thinking. better to be on the higher side of the cya cause then i know i have enough FC vs lower side of CYA and it is actually higher cause then not enough FC.

i just did my cya again since i opened 1 week ago and i got a reading of 40 today and i am very confident. i used the cheater CYA 50ppm bottle sample from test its and looked at the water for the test and i know what to look for. wit the 50 ppm i deff can't see the dot and with my water i can see it. so i went up to 40. and i could barely barely ee it. added a bit more. not to 35 rpm closer to 40 and i can't see it so i am adding more cya to get up to 50 and test again in a week. before i start to add my salt. if i'm at a confident 50 i'll then take it up to 70 or 80 for the salt cell.