Worked within its range! By Steve on 12/8/2016Steve would recommend this product to a friendIt tested as it was advertised. There is a expiration date on the vials, which I didn't expect but makes sense if the standard has to be color specific. They store in a black plastic case that fits the box they come in so they can be protected from light and not fade I guess. The alkalinity and calcium are the same besides there different colors.
Excellent By Donald on 9/18/2016Donald would recommend this product to a friendEasy to use.