I went out yesterday and got Tahitian Moon Sand (there's a thread in the care forum regarding rinsing and everything I did with it.) I put it in this morning and for the last hour, Crumb has been poking at it. He got in, eyed it suspiciously, and began inspecting each piece that wasn't quite black to see if it was food. Now he's touching it cautiously and staring at it, then me, then it, then me. It's sort of funny. I wanted the white sand but when I got to the store it was so fine it was practically like flour. This one's quite heavy and after some good rinsing, didn't cloud the water at all. Here are some photos of Crumb's new substrate and him inspecting it. Some are mildly unfocused but it's hard to get shots of a tank that is no longer reflecting light and a moving fish. I've removed his short front grasses so I could observe him better for now. I'll probably change out Bluey's substrate this week.