Back satin midnight from Petstuff101 is extremely fine gravel, it is not sand. I also have the fine gravel but not the sand and it's almost black depending on the lights shining at the time. If you are buying it for looks then great, if you are buying it for fish with barbels then I suggest not so great but each to his own. The only thing I would now get to make my planted tank base blacker is the Iron Sand concentrate from Swanson Industrial Sands, or a beach if I ever got that far, but for a handful or so that I want, it's not a priority.