From my experience from keeping mostly eartheaters over the last 10 years the Geophagus sp "Aeroes" is definately the most intraspecific agressive geo I`ve kept.
I now have a group of 5 adults in a 2 metre long tank (2 males + 3 females) and there is a lot of chasing and argueing all day.
They don`t defent terretories except from when breeding but just keeps on quarreling all over the tank.
A very beautiful fish though and they do give one hell of a show of posing and stuff when initiating to breed.

I now have a group of 5 adults in a 2 metre long tank (2 males + 3 females) and there is a lot of chasing and argueing all day.
They don`t defent terretories except from when breeding but just keeps on quarreling all over the tank.
A very beautiful fish though and they do give one hell of a show of posing and stuff when initiating to breed.
