I just came home from house sitting for a week leaving my fiance in charge of Dumbledore. Tonight I came home and Dumeblore's tail at the end looks stringy. He just recovered from a rip in his tail (I noticed it right before I left) and it fully healed. I'm going to try and get a good picture but for right now I have this one. I cupped him so I could vacuum his tank up and get a good look at it. Is this rot, or tail biting? I really hope it's neither and it just got caught or torn on a decoration. I did notice the artificial rock I had in there was half floating, half sitting on the bottom so he might've torn it on that or something.
Sorry it's grainy, crappy cellphone picture but I think you get the idea? Any suggestions as to what it could be?