Lately, I have read several threads and been a part of other conversations that seem to employ a common "argument" against ordering Taylor reagents online or, at least, limiting orders to only a specific set of vendors. I do realize that many users like to order from TFTestkits.net and/or Taylor directly and I have absolutely no objection or concern about that (where you get your reagents from is your own business, as far as I'm concerned). However, when interacting with other users, some folks employ the argument that you can not or should not order from vendors on Amazon or eBay because "you just can't trust that they're not selling you old chemicals" or "you don't know how they are storing the reagents".
While those points do have some validity and there may be bad experiences out there, here's what the Taylor website says about shelf life and storage concerns (emphasis from original source)-
In my opinion, I take away two points from what Taylor has written -REAGENT SHELF LIFE
All reagents have a shelf life, whether they are liquids, powders, crystals, tablets, or test-strip pads. If kept dry, powders and crystals are very stable; acids are also long lived. Date of manufacture is not the controlling factor when it comes to shelf life—storage conditions are more important. As with all perishables, reagents are sensitive to environmental influences and will last longer under controlled conditions.
To this end, we recommend:
- Storing reagents at a consistent temperature in the range of 36°–85°F (2°–29°C); extreme temperature fluctuation, say from a refrigerator to a hot car trunk, causes reagents to deteriorate.
- Keeping them out of prolonged direct sunlight. (Note: their brown plastic bottles help protect very light-sensitive reagents.)
- Segregating reagents from containers of treatment chemicals.
- Replacing caps immediately and tightening them carefully so that exposure to air and humidity is limited.
- Avoiding switching bottle caps, placing bottle caps on soiled surfaces, repouring reagents into contaminated containers, or touching test strip pads.
Taylor formulates its reagents to remain effective for at least one year, with only very few exceptions (molybdenum indicator in liquid form is one; after four months old it should be tested against a standard periodically). As a general precaution, replace all reagents more than one year old, or at the beginning of a new testing season.
1. All but a very small number of their reagents are designed to be very stable and so shelf-life issues of packaged OEM reagents are only a minor concern;
2. The way chemicals are stored by a user is the biggest determinant of a reagents useful life. Therefore, since they can not guarantee how reagents are stored once they leave their facility or the conditions under which they are used by the owner, Taylor recommends a 1 year shelf life before discarding.
So in terms of my original concern, I would say that as long as you can find a reputable pool chemical supplier online (and there are several in different regions of the US) that provides Taylor reagents in their original packaging, who you purchase your reagents from should matter little unless they have a documented history of bad service. That being said, private party transactions, such as those found on Craig's List or eBay, could be more problematic.
Finally, the point of this post is not to impugn anyone's choice of vendor, but to try to put to rest the false notion that the shelf-life of an unopened bottle of reagent in it's original packaging is a determining factor in how one obtains their reagents. As always, if anyone has had a particularly bad experience with an online vendor, posting about it would be a most helpful way to inform TFP users. I have ordered from several different sources online with no abnormal results but I have not been using Taylor reagents long enough to have a good enough feel for vendor reliability.