Why does Taylor chlorine test fade after 15-20 seconds but my 'off brand' one doesnt?

[nyvram]

I will take some pics today & post them.

I have a taylor-troubleshooter chlorine tester that requires 2 chemicals to be added and it turns PINK and a generic brand (can't remember the name) uses a single chemical and the results turn YELLOW

I can test the exact same water, at the exact same time, with both kits and the YELLOW will show much more chlorine than the PINK.

If I look right away after inverting the taylor it seems like there is enough chlorine but after another 15-20 seconds pass, it gets lighter until it looks like there is virtually no chlorine in the water at all.

The YELLOW test kit doesn't fade even if I come back a minute later & look at it again.

Do I just have to look fast at the Taylor results or is the YELLOW showing more chlorine in my water than I actually have?

 

[JoyfulNoise]

The test kit you are describing is the basic DPD-only test (R-0001 and R-0002 reagents, pink/red color match). When your FC levels are above 10ppm, the DPD dye will fade and bleach out. The other test you describe is the standard OTO chlorine test (yellow). OTO measures total chlorine (TC = FC + CC) and it does not fade out at high chlorine levels, it just gets progressively more orange.

If you purchase a Taylor K-2006 or TFTestKits TF-100, you will get the FAS-DPD titrating chlorine test which can go to much higher levels of FC (up to 50ppm without bleaching out). Your Taylor trouble-shooter kit is meant to be used when the FC is above 10ppm.

 

[nyvram]

i have the fancy kit recommended by this board to handle doing a SLAM but since the pool is in good shape this year, I keep it inside and ready to go for specific testing.

since all i've put in the pool since late last summer is liquid chlorine, would that be why my FC is above 10? Is your answer that I just need to look quickly at it or should I just be happy with the YELLOW kit showing the chlorine is right in the sweet spot?

 

[JoyfulNoise]

I'm confused? You state you're using some kind of off-brand troubleshooter test kit and now you're saying you have a TF-100 (or K-2006). Can you please be more specific with the details of your testing and can you also post a full set of test results from your TF-100 (the fancy test kit)? Also list or post pictures of the exact reagents being used in the FC test that is giving you trouble.

 

[nyvram]

i have 3 kits:

- 1 little blue taylor kit with the 2 colors that turn it pink
- 1 little blue 'generic' kit with a yellow drop chlorine tester
- the TF-100 (stored inside at the moment) which i dont use right now because i haven't needed those additional chlorine tests for SLAM or anything


make sense? i'll take some pics tonight of all 3 kits.

 

[JoyfulNoise]

i have 3 kits:

- 1 little blue taylor kit with the 2 colors that turn it pink
- 1 little blue 'generic' kit with a yellow drop chlorine tester
- the TF-100 (stored inside at the moment) which i dont use right now because i haven't needed those additional chlorine tests for SLAM or anything


make sense? i'll take some pics tonight of all 3 kits.

OK, well I would appreciate seeing what it is you are testing with. In general terms, I think you are not testing your water with enough regularity, that is to say, you should be using your TF-100 kit for more than just when a pool needs to be SLAM'd. Honestly speaking, if a pool owner is testing and dosing chlorine properly, then a pool will almost never need to be SLAM'd (I have not performed a SLAM in years). Your TF-100 has several important tests that should be performed on a regular basis given that your location (Tennessee) is an area where frequent rainfall can easily cause dilution issues. Roughly speaking, here's a typical/appropriate testing schedule -

FC/CC/pH - Daily or maybe every other day

TA - weekly to ensure proper levels

CYA - monthly or twice monthly depending on if rainfall/dilution is an issue

CH - monthly

Your TF-100 reagents are only good for 12-18months before they are considered expired (some last a little longer), so there is no sense in trying to store them away just for a SLAM.

 

[jblizzle]

Start using the good test kit and then you will be better able to keep the pool balanced.

Do you even know the CYA to know the proper FC level?

 

[JamesW]

The main problem is that you have let the chlorine get too high and it’s bleaching out the reagents.

Therefore, you read the chlorine as low and add more chlorine when it’s really already too high.

As noted above, use FAS DPD more for accurate testing.

 

[nyvram]

i'm confused. my pool barely has any chlorine in it. if i dont put at least a bottle in a day the tests both show clear. its definitely NOT too high.

 

[JoyfulNoise]

So the simple DPD-only test (pink test with two drop style reagents, R-0001 and R-0002) can show a flash of pink then go clear if the FC is too low. And it can show a strong pink color then bleach out to clear if the FC is too high.

But here's the problem, your FC is not stable for some reason and you're not providing us with accurate test results to go on, just a lot of general comments. We can't help you if you don't help us by posting reliable test results from your TF-100.

Also, your FC should never ... let me repeat that ... never fall to zero at any point during the day. You are adding a gallon or more of bleach per day and it is not holding. That suggests your other chemical levels are not right or you have a nascent algae bloom starting. But there's no way we can help you without reliable test data.

When you get the opportunity you need to perform the full set of tests using your TF-100 and post those test results. Do that before you add bleach. Then we can help.

 

[domct203]

i have 3 kits:

- 1 little blue taylor kit with the 2 colors that turn it pink
- 1 little blue 'generic' kit with a yellow drop chlorine tester
- the TF-100 (stored inside at the moment) which i dont use right now because i haven't needed those additional chlorine tests for SLAM or anything


make sense? i'll take some pics tonight of all 3 kits.

You possess the most accurate, and non-subjective chlorine test, a FAS/DPD test, that will answer your own questions in about 5 minutes of your time. Well maybe not 5 minutes, but certainly far less time than it takes to discuss the interpretation of your other two tests.

Break out the TF-100 and let us know what you find.

Dom

 

[YippeeSkippy]

Just a lil sidenote here....with strong concern over the care of your pool and equipment. If your pH is too low (which without being tested you can't know) it takes a toll on the lifespan of your vinyl lining and possibly equipment.

Is 5 minutes every other day *really* too hard to manage?