I currently have a 55 gallon tank, which contains amongst others a Geophagus surinamensis (3inch) and a Golden Severum Heros (3 inch). Over the last three weeks these two fish have begun to fight. It started with the Geophagus chasing the Severum, then they started standing off to each other and they have now moved onto lip locking. Is this a passing phase or are they going to go into full battle mode in the near future.