Like the title says, what is the effective age for CYA test kits? I think mine is 3-4 years old. (Reagent R-0013)
According to my cheapie test strips, my CYA is "at or over 100". But according to the vial test, it is between 60-80, and very likely right at 70. (I ran the test twice and think 70 is the dissapearing point) I of course trust the vial test more, but I do wonder about the reagent age.
Also, in general, how long would all reagents remain effective if stored out of sunlight?