Well, all has been well in my 55 gallon until a few days ago. I have 2 Tiger Oscars around 3.75-4 inches long(Reaching sexual point in life) one is bigger then the other by weight , just a little bit longer. Well the other day I noticed my slightly smaller oscar had nips in the fins and scales are damaged. So I watched them , and the bigger one will kind of ram the smaller one now,sometimes bites the sides of him as well, but the smaller one turns to its side(showing non dominance?) but doesn't really run away, just kind of takes it and continues to follow the bigger one....what should I do? They were best buds until now, and I don't know if this is some mating thing or one is going to kill the other at some point. Thank you.