little rubber lip dude ?

I got two of these guys at the same time, and put one in either of my tanks. When I got them I asked that they give me one I specifically pointed out in the tank, and any other one. The one I pointed out was the biggest one in there, and he's doing fine. He has a larger log he stays in most of the time, and the rest of the time he sticks to the side lodged up against the outside of the cave that my corys live in. The other one I bought was a little smaller, and lasted just about 24 hours. I can't determine why, other than the tank he was in only had two small caves, and my 3" pleco calls one his home... so maybe it was stress related?
 
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