Finally after 15 years of using gravel, I took the sand plunge. Not sure why it took so long. While I was unable to find the black I was looking for (no spectra quartz, 3M or even coal slag around here) I settled on good old PFS. Love the size, if not the color. It gravel vacs quite nice and I do think the fish seem more comfortable on it. Thanks to JamesF for the plant inspiration.