Where do you get fresh reagents?

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jv92red

jv92red

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LifeTime Supporter
Mar 7, 2013
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SoCal
So I received my TF-100 in June of this year and started using it when I went through startup with my PB. (I always keep my test kit indoors) Problem is that my calcium numbers and Alkalinity numbers are consistently higher than his but all other tests are spot on. He is using a Taylor 2005 kit and I was using my TF-100. Since our Chlorine, PH, and CYA #'s matched, here are the tests where there were differences:

Alkalinity:
his: 90
mine:150

Calcium:
his:150
mine: 350

Startup PH was brough down to 7.2 and Chlorine was zero until day 4 it was brought up to a FC of 3. CYA started at 0 but was brought up to 40 over a week's time. Testing went on every day over the first 4 days of startup and while the numbers above for Alkalinity and Calcium changed our #'s were the same difference every time: Mine = 60ppm higher for alkalinity and 200ppm higher for Calcium every time.

This startup guy for my PB is really just a sub contracted pool service and repair guy who has been in the business for 30+ years. He goes through reagents weekly and he has the larger Taylor refill bottles. We did a test in swapping back and forth with his reagents and mine and were able to take out any variability in testing as far as color change point. I used his kit and also came up with his #'s. He concluded that my reagents must be old: R0009 for Alkalinity and R0012 for calcium specifically is what we were able to single out. So needless to say when he started mixing up some calcium powder in a bucket to pour into my pool to bring the calcium up to an acceptable level of at least 250 for start up I was freaking out but I guess I just have to trust his #'s over mine.

So I need to obtain as fresh as possible reagents - where do you all get your supplies? Leslies? My start up guy said to be wary of Leslies as far as reagent supplies for calcium especially as most home owners don't test for Calcium very often so the reagents sit on the shelf for long periods of time. Is there a way to find out a fresh date on these bottles - there is a code on it I just don't understand what it means. Thanks for your help!
 
but I guess I just have to trust his #'s over mine.
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Why? A tenant of BBB is trust your own testing. It doesn't matter how long someone has been in the business, you should learn to trust your testing if you have done the procedures correctly.

Did you wipe the dropper tip during the TA test? That's VERY important with very fresh R-009 or your results will skew high.

When you did the CH test did the color change occur as you expected or was there some interference in the color change that made you question when to stop.

If your reagents are old, then so are many, many others we shipped in June from the same batch. Please PM me your name and address and we will, of course, send you new reagents. I doubt that will solve your issue however.

If you are performing the tests correctly, I am pretty comfortable your results are correct.
 
Any chance did you use the speedstir? The two tests you're in doubt in are VERY touchy when testing by hand. My CH levels (hardest one when testing by hand) went down several points once I started using the speedstir. That large of a difference makes me wonder if maybe the sample wasn't stirred enough during testing.
 
Thanks Dave. This is why I haven't PM'd you initially on this for replacing reagents, rather posting up what was going on cause I feel it must be something I'm doing. I see that the instructions say to wipe the tip every time so I will go and try this again as the Taylor kits don't require this and didn't think this would have as much of an effect.

For the calcium test I waited till there was no color change then paid attention to the previous drop's change and number and counted that as the level. Perhaps there is a fading endpoint issue going on but either result the calcium level is not high as to result in a fading endpoint result or am I wrong on this? Jason's extended test kit directions only mention metal ions being present so perhaps this may be what is throwing me off but not sure why it wasn't throwing off the Taylor test by the pool man.?
 
Thanks Leebo. I think a speedstir is definitely in my future for sure. I hate second guessing this stuff. Especially when my calcium reading was 350 and the pool guy is dumping a bucket full of calcium powder into my pool. No way of getting that stuff out besides a partial empty and I just filled it! :shock:
 
Thanks. At this point I will retry the tests and post those results. If I still come up with the same high results I will then buy some new reagents to try and isolate me as the problem since if new reagents test the same as my previous tests with my current reagents then I would then for sure be the problem.
 
These are the same Taylor reagents for both these tests are they not? I will be very surprised if this is a freshness issue. I have run thousands of these titrations over the last 14 or so years and I have never seen one be bad with older reagents. This includes name brands like Taylor and HACH, as well as generic no names, and private lables from just about everyone. I guess it's possible, but highly doubtful. I will be very interested in the outcome of this one. I think if enough digging is done, there will be error or inconsistency found somewhere. I've seen that scenario repeated more times than I can ever possibly remember.
 

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Try doing this when you retest, while constantly stirring try one drop every five seconds or so and see what your results are. If they're the same, then I'd question his test results. It sounds like maybe his test kit could be dirty, and spitting out drops larger than yours.....thus tossing off his results. The more I think about it, his reading if the CH at 150 is the lowest I remember ever seeing from out west.

If you end up around where your results were....ignore his tests and trust your own. A speedstir won't be a bad investment however.....promise you'll love it.
 
Don't some of the reagents come in different strengths were a drop in one reagent is designed for use with a 10ml sample and in another reagent, for the same test, is it designed for a 25 ml sample?
 
Don't some of the reagents come in different strengths were a drop in one reagent is designed for use with a 10ml sample and in another reagent, for the same test, is it designed for a 25 ml sample?
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Absolutely not. At least not if it's Taylor chemistry....used in both the TF-100 and the K-2006.

If you buy R-0009 from TFTestkits or any Taylor dealer....it's R-0009....period.

Same with all the other reagents.
 
ok - I did some retesting after I got home today from work and here are the results (PB came by while I was at work and adjusted chems and let me know the values)

Calcium = Now spot on. PB measured 240 today, I also measured 240.
So I retested but this time I stirred for at least 5 seconds between every drop of every reagent. The key for me was noticing that in earlier tests the water would turn from pink to a clear color but there are those 50 little fleshy pink blobs suspended that separate out in this test that stay pink when the water turns from pink to clear that I kept adding reagent to change them to blue which would make the water blue so I was waiting for that end point which was the error. What I noticed now was that the water itself was changing from pink to clear around the 23 drop mark. Drop 24 went slightly more 'clear' color but additional drops would not change the color of the water from 'clear' to 'blue' but would continue to lighten up the pink fleshy blobs. The pink fleshy blobs wouldn't turn from clear to blue until after the 30 drop mark. Problem then was that the water was still clear and not 'blue' like I was waiting for so more drops to turn the water 'blue' hence the 35 drop end result in earlier tests. What I now understand is the definition of 'blue' in this test is really what looks like clear water with an ever so slight light blue tinge. I tested my tap water and it is indeed 150ppm. This matches up with what my startup measured by the PB the first day of start up.

Alkalinity = decreased difference from 60ppm to 40ppm which still leaves me stumped. Today PB measures 90ppm, my results are 130ppm
So on these retests I again stirred for at least 5 seconds between every drop in every reagent application, wiping the tip of R-0009 after every drop. This test's end point is much easier to recognize than the calcium test. Drops 1-11 of R-0009 make no change from green. Drop 12 changes from green to clear. Drop 13 changes from clear to red. Additional drops have no increase in red.

So Alkalinity while improved still has me stumped on why a difference. I plan on getting another vile of R-0009 and if it tests the same as my current vile then it must be something I'm doing that is wrong. Anybody have any suggestions?
 
Add a bunch of titrant reagent drops (say, 10 or 20 of them) at the start of your test before you add the calcium buffer or indicator dye. You count those titrant drops as part of your total (i.e. add them to the number you do during the later part of the test). That should help reduce what is called the fading endpoint, but it can also help reduce the amount of those floating bobs you see. This is described in the Extended Test Kit Directions:

The sample may turn purple during the test, or go to blue for a moment and then turn back to red/pink. This is called a "fading endpoint" and is caused by interference from metal ions. If this happens, do the test again, but this time add five drops of R-0012 before adding any R-0010 or R-0011L. Remember to count the initial five drops in the total.
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Big thumbs up to Leebo for insight and help on this one. I've trained a lot of guys to run these tests and he is clearly better at thinking this through over the computer than I. Why I didn't think to advise that is beyond me.

On the TA difference, I would still trust your numbers over his. Again, Leebo is onto something, and this time, with the drops. That guy could have the wrong dropper tip from a replaced tip or old bottle that makes too small a drop size. Unless of course there is a possibility of something wrong with your tip. Not possible you replaced it or cleaned it out by poking something in it is there. I highly doubt this, just covering bases. Another possibility is making sure you are holding the bottle completely vertical when you add the drops. Make sure you aren't holding it tilted. Not assuming you are, I am just covering all bases. I may get in trouble on this, but I add extra drops for the calcium test to see the end point better. I'll put 6-7 drops in and I do it based on my work experience. A surprising lot of folks have tough times seeing endpoints and this helps a lot of them. Two extra will not skew the results and it makes for a more vivid endpoint. You can make sure of this by completing a test with normal drops of indicator and then drop in a couple extra when you are done. If you have reached the endpoint, the color won't change, but turn a darker blue. I pray I won't be out of line with the forum on this, as it is not suggested that I know of. Again, this is for the color indicator ONLY. If you veer off the instructions for the other buffers and titrants, your results will be wrong.
 
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