Why is this such a big deal? If that's the only replies I'm going to get then I'll just tell you, it's a 125! Now can we please move on to the question of which fish is everyones' least favorite?
You just screwed yourself, now you won't get one single answer based on the fish they personally like the most. My answer stands though I don't think 125 is too small for that many fish no matter what you get rid of provided the filtration is good which from looking at pictures of your oscars it is.

