I read the other reviews and bought it anyhow. There really is no science to this at all. There's also no real fizz to the fizz balls you make for the bath. Directions are poor -- to the bath salts you can add any herbs of your choice, but they give no guidance on which herbs might blend well with the lavender or peppermint oils. Then, there's getting the herbs out of the tub and out of your hair....There are not enough ingredients even to make one of each item discussed in the directions. Rather disappointing, actually.