I have made those basic ones before...they work fine as a first-time-making-fizzies sort of thing, but I quickly found that adding some other ingredients made them more interesting (and made them last longer in the tub). I add a little olive oil and a bit of cocoa butter so that it's a more moisturizing bath, and I also add a little polysorbate, which allows oils and water to mix together. What that means for the bath is that you don't have fragrance oil, (and olive oil and cocoa butter if you add those) floating around on the top of the water as you're sitting there. It also means there's a lot less of a ring around the tub afterwards! The polysorbate also slows down the fizzing, which is helpful because when I do just the basic recipe the fizzie only lasts like 30 seconds. Hope this helps