Well, it's probably going to want higher light eventually, but give it time to adjust. I'd say in a week or two, move it a little higher. While it can grow it's skeleton out of loose Calcium and carbon in the water, it will probably do better with a rock to encrust upon as a base.
Recap: If there is enough light to stay there, fine, if not, move it higher after it has time to adjust. It can grow on the substrate, but will also encrust on a rock very nicely.