I have a 5" Oscar in a 30 gallon, thinking he's a male from his vent. I will be moving him to my 75 gallon soon. Someone was giving away a 4" Electric Blue Acara, so I put him in my 30 gallon with my Oscar. My Oscar has never been agressive towards any of the other cichlids he has previously tanked with (Jack Dempsey, Blood Red Parrot). But he keeps rubbing against the EBA. Is this a sign of aggression? Trying to mate? I want to make sure they get along or I'll need to move the EBA.