Two of my Otos were stuck to the glass today and one was obviously thinner. When I looked closer, at first I thought I was seeing it's ribs because it was so skinny. Then I realized that didn't make much sense and then... OMG, it's a worm. Please tell me it's not. I don't know what else it could possibly be. Or what to do about it. I got this Oto about two weeks ago. There's a set of 4 in the tank there were all bought together. No other fish - just red cherry shrimp.