Is there another (better more accurate) test available for CYA aside from the ole' watch the black dot dissapear?
Better CYA test?
- Thread starter FloridaPoolNewbie
- Start date
- May 3, 2014
- 58,581
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Sorry - but this has been asked many many times.
No. For the residential pool owner, the R0013 melamine test is the best there is.
No. For the residential pool owner, the R0013 melamine test is the best there is.
- Jul 21, 2013
- 53,045
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Nope, not better and more accurate. If there was we would be recommending it.
If my other tests are the same as Leslie's, can we trust the one at Leslie's? It's a digital test..... I don't know how often or if they calibrate the machine.... I really don't trust myself with the CYA test. Honestly, I like their CYA number better than the one I came up with.
BenB
Gold Supporter
- Jul 24, 2020
- 277
- Pool Size
- 19500
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
And I like the weight shown on my driver's license more then the one my bathroom scales tell me.... Doesn't make it accurate
- Sep 23, 2015
- 1,593
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Astral Viron V25
Welcome to the forums Btrimble.
That is the elephant in the room. Your tests wont always be the same and there will be variances between stores. The store tests produce a digital readout but the tests are a colorimetric chemical test that are evaluated with photo optics which then produce an adjusted digital readout. They have limitations, calibration is an online manipulation of the conversion factors rather that the tradition standard solutions, in essence they are a glorified test strip. The extra decimal place is an illusion that instals confidence but it is generated by the final conversion to digital and has no connection to the original chemical test.
I hear you with the CYA test, if Hanna produce a CYA Checker I would use it but with a little practice your results will be more reliable than the store test. In the end it is the reliability of good home testing that the folks hear rely on to offer the best advice.
- May 23, 2015
- 24,459
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
You can certainly purchase an extremely accurate and precise digital CYA tester from Hach … and it comes in at the low, low price of only $350 (not including the reagents you need to do the test as well as the calibration standards you need to use before each test to ensure accuracy). For around $600 or so plus a trip back to the manufacturer once a year for recalibration & certification, you can get an accurate measure of your CYA to the +/- 0.1ppm precision …. which is entirely unnecessary for a residential pool. Or, you can stick with the $10 melamine disappearing dot test, practice consistency, and be within the +/- 10ppm ballpark which is more than accurate enough to keep your pool sanitary and clean.
Katodude
Silver Supporter
- Aug 22, 2017
- 2,620
- Pool Size
- 15000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Ahhhhh, I wish you had not posted that. Now all I want is the Hach digital precise CYA tester!!!! Just another sleepless night now, dreaming of things I cant have.
- Jun 7, 2017
- 9,134
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
The main issue is that the test instructions from Taylor are wrong (in my opinion). The dot does not disappear. If you add drops until it disappears you'll have a CYA level higher than you think. See below for what you should see. I highly suggest you get the 50ppm test solution so you know what you should be looking for.
Attachments
- Feb 6, 2015
- 6,172
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
If you keep adding the mixture to the test tube, you will have a CYA number LOWER than you think. The more solution in the test tube, the LOWER the reading.
- Jun 7, 2017
- 9,134
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
Ah yes, but, once you get that lower number, you add CYA, increasing the number.
TF100 
soon for us but for the last year and 4 months Aquachek 7 ways (CYA) have matched Pinch a Penny readings. I then use the TFP CYA/FC chart to set my FC...water xtal clear. We only use liquid chlorine(1.59 per gallon bulk local ACE hardware) and occasional muriatic acid after hard rains.
soon for us but for the last year and 4 months Aquachek 7 ways (CYA) have matched Pinch a Penny readings. I then use the TFP CYA/FC chart to set my FC...water xtal clear. We only use liquid chlorine(1.59 per gallon bulk local ACE hardware) and occasional muriatic acid after hard rains.
I agree, the best thing is to buy the 50 ppm standards and run the test with that, see what I looks like when it’s complete with your own eyes in your own lighting situation.
Everyone hates this test though. If there was an $80 meter that have good results like my Apera PH60 PH meter I’d have it already.
Are you suggesting your picture is where you measure "not seeing the dot"? Because I still see the dot.
- Jun 7, 2017
- 9,134
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
That CYA test was using the 50ppm test solution. The dot is for sure visible. Adding CYA until the dot disappeared would have put CYA at 40. I would have then added more CYA thinking it was lower than it actually was and ultimately ended up with a higher CYA level than I thought. Now if I was targeting 90 since I have a SWG and at the same time targeting the low end of the Chlorine level, I'd have a problem.
- Jun 7, 2017
- 9,134
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
I actually disagree with this. I don't hate the CYA test at all. If Taylor had said add solution to the test tube until the dot is just slightly visible, it would have been much easier. The "until the dot disappears" is the problem. I don't view this test as hard at all. I also disagree about changing lighting conditions make a huge difference. I looked at the sample in different lighting scenarios and saw basically the same thing in all locations.
I think the tf-100 should include a 50ppm test sample with the TF-100 kit. It doesn't have to be the giant bottle that you get when you buy it outright it just needs to be enough for maybe 1-2 tests.
- Nov 30, 2019
- 855
- Pool Size
- 8500
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Or just a photo of what it really should look like at end of test.
- Jul 21, 2013
- 53,045
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
- Nov 30, 2019
- 855
- Pool Size
- 8500
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
In that photo it looks like the dot “disappeared “. I think we’ve concluded that is an inaccurate indicator of end of test. The 50ppm standard indicates the dot will still be slightly visible.
- Jul 21, 2013
- 53,045
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Whatever. Really does not make a big difference. You stop with the dot a bit visible and you set a higher CYA and higher FC level. The whole reason for measuring your CYA is to set your FC level. A bit higher FC is better then too low.
Your CYA level alone makes little chemical difference in your pool.
Your FC makes a big difference in your pool.
Similar threads
