what disease is this?

[creep]

I got a pair of clowns from teh LFS store on Friday. When I got home I realized one of them had chunks of the fin missing. The other one was fine though. They both swam around and looked good otherwise. Then the last couple of days the one with the bad fins started to breath heavy, stay at the bottom of the tank, and not really swim. He also isn't eating. Does this sound like brook, fin rot, or something else? Whatever it is, how do i treat it. My other clown looks healthy for now. Here is a pic of the clown in question.

[SAT]

It smells like Brook. Here's a link that may help:
http://www.petsforum.com/personal/tr...oklynella.html