Is this a common pleco?

looks like a common, though i can't tell which species exactly. hope you got a big tank.
 
A 55g probably isn't going to be big enougth as common pleco's can grow to 2 feet in length.
i;ve never seen one over 16", though im sure its possible for them to grow that large. his 55G will probably be OK as long as he's not OS.

back on subject... yeah, that looks like a common to me, probably a gibbi.
 
I've seen one that was released into a pond in Florida and caught by a kid fishing that was at least 18".
 
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