Good, it's what is done to save light with T5 lights, but my guess is that the Radion led light are correctly developed to focus the lighs from the surface to the deep of the tank. I use the lateral side and the deep position for the soft corals that cannot stay too long under the 100% of the potential Radion's PAR and power, and the central position for the SPS corals, that get the best of the direct pumps and lights. The light spill shades are perfect because where it must be stop the unwanted light it does (out of the tank), and it reflects a bit for the smooth sides surface the light. The Radion diffusers are pretty useless IMHO.