Hi! I have a question about bath bombs. Mine fizz out very fast and am wonderIng if any of you may know what I could use more or less of to get a slower fizz? My dry mix is 1 cup baking soda, 1/2 cup each of citric acid, cornstarch and Epsom salt for the dry mix, every other property is perfect, just the fast fizz that I don't like. Any advice welcome!