Last night I noticed my biggest FBT was not in the tank. I looked everywhere in the tank and in my little apartment. Is it possible he buried himself, perhaps to hibernate? I didn't think they did that. Burrowing I mean. I want to know if that is a possibility before I tear up the substrate. I am sooooooo bummed out. I looked on the floor and under EVERYTHING for an hour. I don't know how he escaped. boooo hoooo hooo!!!!!! : - ( sniffle!