not to be a jerk, but all the abbreviations are sorta annoying. Call me stupid, but it's tough to immediately figure out what a BP, FM, and O is, and then harder to help you.
I've never really been a fan of seeing Oscars in 55g tanks, but I suppose it could be done. With other fish in there, you'll be changing a lot of water. And by "a lot" I mean 50+%, 2-3 times per week just to keep them alive. Expect health problems that take a long time to go away (fin rot, etc.). My .02 anyway.