The 7 species of the Fish Class belong to the Orders:
- Astronotus ocellatus, Oscar, Order: Perciformes, Family: Cichlidae, origin: South America
- Cichlasoma nigrofasciatum, Order: Perciformes, Family: Cichlidae, origin: Central America
- Cichlasoma meeki, Order: Perciformes, Family: Cichlidae, origin: Central America
- Xiphophorus helleri, Xipho, Order: Cyprinodontiformes, Family: Poeciliidae, origin: North and South America
- Danio rerio, Zebrafish, Order: Cypriniformes, Family: Cyprinidae, origin: Asia
- Paracheirodon innesi, Neon, Order: Characiformes, Family: Characidae, origin: South America
- Hoplosternum thoracatum, Hoplo Catfish, Order: Siluriformes, Family: Callichthyidae, origin: South America
