Do test chemicals expire? Should I replace mine?

[CarlD]

Actually, the cold isn't bad for them. It's heat, humidity and sunlight that destroys reagents. If you keep them cool, dark and dry they last much, much longer. All of my test stuff lives in the house for just that reason.

Poconos actually refrigerates his refills to keep them lasting much longer--but he doesn't have kids--many of the reagents are poisons.

[waste]

Good point about keeping the reagents out of children's reach, Carl!