The brown knife fish and rope fish will get fairly big. I don't know if they would do okay in a 55 gallon. I am sure someone will come by and give you more help.
So far so good except i am not sure about the rope fish. Brown Knif fish can get to 12" and should be fine in a 55. ypu should be ok except for maybe the glass cats but they school i think so you should be ok.