TF-100 test kit and reagent life expectancy.

[y_not]

I was curious as to the true life expectancy of the reagents in a good quality kit like the TF-100.
Assuming they're kept in a dark, closed cupboard, inside the house /w no extreme, but just gradual temperature changes, what sort of lifetime can one expect out of the reagents?

Please note, I don't have AC, but we keep it a good 10-15deg. below the outside air temp during the hotter parts of the summer.

I'm a little confused, as many kits, and even on TFTestkits.com, it says to replace your reagents every season. That seems a little excessive to me, IE. highly expensive and seemingly unnecessary. Seeing as the chemistry should contain stabilizers if needed and the mix is tightly sealed and not exposed to the sun, except for brief periods in daylight when testing, but I do bring my samples into the shade for testing anyway.

What are your thoughts on this?
I'd sure hate to have to spend nearly the price of the kit each year, just to replace the reagents.

Note: I did see JasonLion's post on each of the tests/chemicals and how to tell if they're bad, like say /w the phenol red, or abstract color changes.

 

[frogabog]

FWIW, the CYA reagent I'm using is at least 18 years old (dad gave it to me). Left it outside every year too. I have 18 year old TA and CH reagents that are also just fine (have compared with fresh reagents). I bought new CYA reagent last year but have yet to use up the old stuff so I haven't even busted it out.

The R-0870 is light sensitive, so that could go bad but if kept in decent conditions it too will last a long time (CYA seems to last forever though). The information says to replace it yearly... but most of us don't unless the test results show wonkiness. I've heard Dave from TFTestkits even say out loud (in the forum lol) that he doesn't replace his yearly either.

The TF100 should serve you at least two seasons, if not more. Only buy the replacement reagents you need. R-0870 and R-0871 probably go the fastest out of all of them.

 

[y_not]

Haha, cool. I wondered, good info.
Thx.

WOW! 18 years, granted it was your dad's, but how long have you had a pool?
Oh, and about how many tests do you get out of the FAS-DPD powder & reagent?

 

[JohnN]

If anyone will find out how long they last, it will be me. I bought 16 oz R-0871 and R-0013, and a 1/4 pound of R-0870. I am keeping them in a nice, dark closet, so hopefully they last. If not, I guess next time I will get 2 oz bottles.

 

[frogabog]

A spa (octagonal, fiberglass, orange... with the 80's style decorative tile ring... remember those?) was given to us, oh sometime in the year 1993 . After it sat upside down in my back yard for 5 (edit: I've been told we didn't have it 5 years, it was installed in 95) years we decided to give to dad. Apparently he found this used kit online (ebay most likely). The reagent bottles are massive! Each one is probably 5oz. I got the kit 3 years ago, and figured it to be at least 15 years since he bought it used.

18 years old. Minimum. :~}

I bought two containers of R-0871 last season (well, 3... but I spilled one whole bottle on the patio). I tested with it almost exclusively and have since given away my OTO test block since I don't need or want it. This season, I'm still working on the first container of powder and I'll probably get at least 2 more weeks out of it.

I used almost a whole 2oz bottle of R-0870 though. This season began with it 1/4 full so I bought another locally. So far... I've not busted out the new bottle of reagent either.

I didn't have to shock my pool though (well I did once, but it was over in 12 hours and held shock level after the first 2 hours so I didn't have to test a lot - probably doesn't count insofar as reagent use). If you might need to shock, more reagent will benefit. Testing at shock levels for a length of time can deplete reagents much faster than daily or a few times a week testing. Get the largest bottles you can for value sake, and of course for reducing the chance of having to re-order mid-season.

Keep in mind it's hard to say how many tests are in a bottle due to the fact that most days you'll use 12 drops per test (6ppm), but should you ever need to shock you could be using somewhere around 30 or more drops per test (15ppm), and you'll test multiple times per day. On average however, 1 container of powder and 2oz of reagent will be plenty for one season.

 

[UnderWaterVanya]

Without the OTO how do you test pH or were these separate in your kit?

 

[frogabog]

I have a taylor block, and reagent. I use that most often anyway. A friend needed something to test with... I gave her the block and reagents from a hth kit.

 

[y_not]

Thanks for the helpful data...

Frogabog

As always.

Yeah, I thought that math was a little off, but I wasn't going to question it, as I knew what you were getting at and trusted your total was right, so that's good enough for me.

When you're doing a shock, isn't it such that you can simply reduce the sample size you're using from the pool, thus reducing the ammount of reagent you're using?
*Grammar check* Is it re-agent or reagent? :-|

Also, I saw you post in another thread about a wider range color block that you were using for pH testing, one you felt was much easier to read?
I was sure you had mentioned a Leslie's block, but now I'm not so sure, seeing as you have said you use a Taylor block.

 

[y_not]

BTW, My niece gets a kick out of your username 'frogabog', she laughs when I say it. I think it's very creative and gives me a chuckle too. :lol:

 

[JohnN]

I'd like to hear about the pH block. I always find the Taylor one almost impossible to read. Then again, I also found the hth one impossible to read. I guess I just hate pH.

 

[y_not]

I'd like to hear about the pH block. I always find the Taylor one almost impossible to read. Then again, I also found the hth one impossible to read. I guess I just hate pH.

I'm with ya man, there needs to be far more gradients on the block and the density needs to be more accurate. Maybe a shade behind the test vial?
Have you tried a drop of the Taylor acid demand re-agent?
This brings it down into the oranges, so you can more easily tell.
There are instructions on Taylor's site on how to do this, I can go find the link if you'd like.

 

[Lana537]

Call Taylor!

Hello All~~

Once a year I call Taylor, speak with a human being there, and we check through the lot numbers on all of my reagents. She tells me whether they are "Fresh" or "Usable". (I have never had one so old that it got a lesser evaluation.)

Call them!

Lana

 

[JohnN]

I'd like to hear about the pH block. I always find the Taylor one almost impossible to read. Then again, I also found the hth one impossible to read. I guess I just hate pH.

Have you tried a drop of the Taylor acid demand re-agent?

Sometimes I do that, but I guess most times I just forget. Usually I just say "Ok, not 7.2, not really 7.6, so... I guess 7.4." It is never too low or too high, so I don't care if I am not perfect. I have to remember to use the acid demand.

 

[y_not]

Sometimes I do that, but I guess most times I just forget. Usually I just say "Ok, not 7.2, not really 7.6, so... I guess 7.4." It is never too low or too high, so I don't care if I am not perfect. I have to remember to use the acid demand.

Yeah, JasonLion & ChemGeek really seem to stress that the pH doesn't matter whether it's 7.5 or 7.6, so long as it's within range and your results are consistent. Only you can tell when it changes, you'll see it. I know I have.

They say this about FC and pretty much every other test too. WHo cares if it's 43ppm CYA, it's 40, K? LOL

I agree, but it's hard for us OCD types.
But I have learned I just have to let it go with things like that sometimes.

But I'll admit, sometimes I think it's rosy pink /w purple, which is really too high for the majority of pools. But then I test it in true daylight and it's red. UGH!!
So I just go with that and call it good. Bad, bad OCD!! Shut up!!
HA

EDIT: This link was super, super helpful for me.
pH Test Block Colors