Keep in mind that a mature tank with lots of biodiversity and microfauna will take care of this a lot better than a sterile tank with only some bacteria added. The mature tank will quickly consume any ich tomonts/cycts (or whatever) that hit the sand... food is food for these critters. This is why people have always said that mature tanks are easier to keep fish in, even though most people think that it is because of stability. Sterile tanks just provide a breeding ground for the ich.
I totally agree.