I have noticed that when I first open a bottle of Flourish it has a light brown color and not opaque. By the time I finish with it, it has turned dark and has precipitates in the solution. For all you chemists out there, what kind of reactions are we looking at? I assume there are oxidative products being formed causing some of the chemicals to precipitate. Does anyone know if the efficacy of the bottle is compromised from this? I have always kept the opened bottle refrigerated.