Ok, so by "bad chemistry" do you mean too much chlorine? It seems the majority here say too much acid will not cause color loss, but chlorine will if the blue pigment is not colorfast. It also seems according to the supervisor's on-site test, that my calcium levels are between 600-700 ppm, although a sample taken to Leslie's the same day only revealed 339 ppm. I sanded a sizeable area on the front step yesterday which only revealed the midnight blue color. Today, there is a whitish film on the treated surface. Additionally, the loss of color took place only 40 days from the date of application...in no way should that be considered something happening "over time" unless there's material defects or some kind of very unique chemistry reactions going on.If it really is a plaster product I assume it will have the same type of susceptibility to bad chemistry as your current plaster, unless your current plaster was just faulty. When my parents had their pool replastered, you can see the dark blue is kinda splotchy. I wonder if that’s just the thing that happens over time.