Hi Inez, I have been using this wax for about a year now. I have never added anything to it. The only time I had any "cracks", was when I poured too hot,cooled too fast, or the jars were too cold. And the cracks always showed up right away. I have found that I have to adjust my pouring temps according to the weather ( right now when it is warm, I can pour warmer, ~125) HTH