Reagents that are stored properly maintain have a much longer shelf life and maintain their maximum effectiveness than those that are improperly stored. This includes all reagents including liquids, powders, crystals, tablets and test-strips.
Reagents should not be stored in moist or damp areas and should be kept dry and moisture free at all times. Powders, crystals and acids are very stable and have an excellent shelf life if kept dry and aren’t exposed to sunlight.
The date of manufacture is not the controlling factor when it comes to reagent shelf life; the storage conditions are much more important. As with all perishables, reagents are sensitive to environmental influences and will last longer under controlled conditions.
Taylor Technologies Recommends the Following Care for Reagents
Storing reagents at a consistent temperature in the range of 36°–85°F (2°–29°C). Dramatic temperature fluctuations, such as being stored near a refrigerator or in the trunk of a hot car, causes reagents to rapidly deteriorate.
Avoid exposing reagents to prolonged direct sunlight. Most manufacturers use brown plastic bottles to help protect light sensitive reagents for this very reason, but prolonged overexposure to direct sunlight will quickly deteriorate any reagents effectiveness.
Keep reagents separate from other non-reagent water treatment chemicals.
Replacing reagent caps immediately after use and tighten them carefully to limit their exposure to air and humidity.
Don’t switch reagent bottle caps. Placing bottle caps on soiled surfaces, re-pouring reagents into possibly contaminated containers and touching test strip pads can easily contaminate reagents.
The experts at Taylor formulate their reagents to remain fully effective for a minimum of one year, with very few exceptions.
As a general precaution and rule of thumb, you should replace any reagents that are more than one year old or at the beginning of each new testing season.