My brother raised them in a large aquarium, I believe it was a 125 gallon. He had them flown in and picked them up at the airport. I can remember him having lots of smooth rocks stacked high to make caves and hiding places. He kept the Acara's by themselves with no other types of fish in the tank. When they are fully grown they are stunning. They did not pick on one another and are not relentlessly aggressive like convicts.
I would guess that you have to special order these fish to make sure you get exactly what you want. My LFS
sells something called a Dwarf Acara, but they do not ge them often or in many numbers.
I hope this helps. It has been years since he kept the Acaras, but I still hear stories. Good luck!