The giant gourami (lat. Osphronemus goramy) is the largest fish from all gourami species kept in tanks. In the wild, it can grow up to 60 cm (24 in) long and even larger, according to some data. In tanks, it grows a bit smaller, about 40-45 cm (18 in), but still, it is a very large fish.
The Jack Dempsey fish (lat. Rocio octofasciata, earlier called Cichlasoma octofasciatum) is a widely spread tank fish within North and Central America. Because of the fish’s congenital aggressiveness towards its tank mates, the USA aquarists have called it Jack Dempsey by the popular professional boxer’s name.
Nothobranchius or notho killifish is an African freshwater ray-finned fishes genus of the Nothobranchiidae family of Cyprinodontiformes unit. These are the most bright-colored fishes among those that are kept in a tank. Their main distinctive feature is their unusual lifecycle, which is evolutionarily connected with the rain season arrival.
Fire eel (Mastacembelus erythrotaenia) resembles a true eel, that’s why the fish got its name. However, this fish has nothing in common with eels despite its snake like body and pointed snout. This is a renown tank and commercial fish.