I have noticed some people, but not many using foil iver the soil to reflect light back up to the plants. This seems like a bad idea to me, as it would limit airflow across the soil, and down to the roots. However, would it be of any benefit to use a thin layer of perlite on top of the soil to reflect light back of to the bottom leaves? I just though since it is white, it should reflect light back up better than the dark soil. So, viable option, or complete freaking waste?