Tried it along with gravity, about 4 weeks into flower. There was a bit of color change on my skywalker, but nothing on my white widow. I stopped using it because half way through my next run there was a white mold that formed in my bottle, even when I was keeping it in a dark closet that like 75*f. Overall I wasn't that impressed, and for the price it didn't seem worth it. I did however like using Gravity, I could tell a difference in the buds for sure.