For those interested further in the black sand, I put the CaribSea Arag-Alive Hawaiian Black in my tank. This sand contains some white and red sand, but mostly black. The coloring gives the sand a feeling of a terrazzo floor richness. The black appears to be both a black sand and obsidian, which is a volcanic glass. Sizes are listed from .25-3.5 mm. The whole aquarium shimmers well under a Kessil and I can see shadows of the waves and rocks on the surface of the sand. The sand itself lays down well and looks kind of carpet soft to me. I'm glad I went with the black. Thanks everyone for all your help!