Liquid MSU Fertilizer - Old bottle - Still good?

[MT-Phal]

I found a bottle of MSU fertilizer, well water formulation, that I purchased from Ray's store maybe six or seven years ago. The bottle is opened and almost empty; I must've used most of it and then placed it somewhere and forgot about it. Do you think it's still good to use? The liquid seems a bit bluer than I remember it being but that could be from becoming concentrated since it's the bottom of the mix.