I really don't think its mucus, its not slimy at all. It feels like dried soda or something on him, lol. But it smells like wood, so...I dunno. As far as the scale rot goes I'm gonna keep a close eye on it. The shelf liner I was using before would stay kind of moist at times so he would be sitting in a moist environment. Which is partly why I changed to Aspen bedding. If the scale rot does not clear up by next shed or gets worse I'll let you guys know. Thanks again!