My reagents are kept in a dark, cool, dry cabinet and I have never had a problem with them degrading, with the exception of the DPD-FAS powder, which is going to degrade anyway. (Even that I can usually get the equivalent of two seasons out of, most of the time--I use it year round, so I buy it in bigger bottles than the ones that come in the test kit.) Most of the reagents I have are directly from Taylor, and I have stored some in that cabinet for at least two years, with no reduction in accuracy when compared with a new bottle of the same reagent. I think my fellow mod, Poconos, keeps his CYA reagent in the refrigerator, but I keep mine in the same cabinet as the other stuff.

Janet