Replacing test reagents - lifespan?

Glock · Sep 3, 2012

I am replacing some reagents and I am tossing around the idea of buying 16oz bottles of them to save money. Are there any reagents in the Taylor K-2006 that I should not buy like this? It's not like the pool is going anywhere so I figure I might as well buy them. I used all my R-0871 shocking my pool over the past week so I have to order soon.

I store them in a cool, dark and dry place.

257WbyMag · Sep 4, 2012

If you store them in a dark place indoors, they should last for several seasons. The R-0011L solution can get old and may need replacing in a few years. Other than that though, you'll probably end up running out of things before you need to throw them out. One thing that I would suggest buying in a larger amount is the CYA reagent. Since you use so much of it for one test, it pays to go bigger. tftestkits.net is a very inexpensive place to get such items.

Bama Rambler · Sep 4, 2012

The only thing I'd even consider buying in that quantity would be R-0871 and a 2oz bottle is more than I use in a season so it'd be questionable. Taylor says they're good for a year, so do you really want them sitting around 3 or 4 years? I figure about 2 years is all I want to trust them.

chem geek · Sep 4, 2012

Generally speaking, the organic dyes are relatively fragile (R-0004/R-0014, R-0008, R-0011L), the FAS-DPD liquid is light/heat sensitive (R-0871) and the DPD powder is moisture sensitive but is also an organic dye though more stable in solid form (R-0870). The acids/bases should last forever (R-0005, R-0006, R-0009, R-0010) while the other components are in between in stability (R-0003, R-0007, R-0012, R-0013).

JohnN · Sep 4, 2012

So you would not recommend getting 16 ounces of R-0004,R-0008, or R-0011L, correct?

Glock · Sep 4, 2012

I ordered the 2oz R-0871. I will see how much I use the first couple of seasons before I order large quantities.

chem geek · Sep 4, 2012

JohnN said:
So you would not recommend getting 16 ounces of R-0004,R-0008, or R-0011L, correct?

That's right. Not unless you plan on going through that volume of reagent in no more than 2 years (Taylor recommends changing after 1 year, but storing in a cool dry place away from sunlight probably is OK for up to 2 years). See the Taylor article on Recognizing a Compromised Reagent.