The most aggressive pet fish is the Wolf Cichlid (Parachromis dovii) as well as the Red Devil Cichlid and the Hoplias aimara (Wolf Fish).
These fish are territorial beasts and are highly reactive and grow up to 2 to 3 feet long and will also attack anything they share a tank with relentlessly.
The Wolf Cichlid (Parachromis dovii) is one of the largest cichlids in the world.
Males can reach massive lengths of 24 to 30 inches (60 to 76 cm) and weigh up to 14 kilograms (30+ lbs) in the wild.
In captivity, they commonly grow to about 18 to 24 inches.
Females are significantly smaller, generally maxing out around 12 to 16 inches.
These fish grow incredibly fast—often hitting 12 inches within their first year.
These fish grow incredibly fast—often hitting 12 inches within their first year.
Due to their immense size and extreme aggression, a single adult Wolf Cichlid requires a massive aquarium, usually starting at a minimum of 180 gallons for a juvenile, with 240 to 300+ gallons recommended for a fully grown adult.
Red Devil Cichlids (Amphilophus labiatus) typically grow to between 10 and 15 inches (25 to 38 cm) in length.
Males grow larger and more robust than females, and in the wild—or in optimal conditions with large tanks—they can occasionally reach up to 18 inches (45 cm).
Hoplias aimara, also known as anjumara, traíra, trahira, manjuma, anjoemara and giant wolf fish, is a species of freshwater fish found in the rivers of South America.