Does anyone have experience or wisdom to offer on growing corals that prefer low light in tanks with strong lighting? The ideal solution for me would be some kind light filter that decreases the intensity of light in part of the tank, so you could have high- and low-light corals in the same tank. There are neutral density filters for cameras, which makes me think that there are coatings or materials one could put over some of the lighting to tone it down for this purpose, but camera companies are not likely to be open about their composition, and even if they were they are likely to be beyond the hobbyist's capability.