What's up with this bass

[Cu455]

What kind of bass is this? It is larger and looks different then its tankmates. Is it different looking because it's stressed or is it a different type? I asked the worker about him and he told me that he never noticed him.

[video=youtube;H26DeHPw34A]http://www.youtube.com/watch?v=H26DeHPw34A[/video]

 

[mralbin123]

looks stressed

 

[colaxy]

should be a stressed mono