Haven't found the little guy yet. The bigger shrimp is swimming around and eating stuff. My tetras will run into his antenna and the poor shrimp will jump. The fish don't harass the shrimp at all. The little shrimp looked different than the bigger one. I didn't even think that he may be molting. I haven't seen any shrimp bits around the tank. I'm wondering if he's stuck somewhere, dying. Who knows, maybe he tried to get underneath the gravel and now he's stuck. I'll keep an eye out for him. If I don't see him in a week, I'll consider him gone. There's lots of little hidey-holes in my tank, so he may just be hiding/molting. I might get up one night and give the tank another thourough look.