Oscar

Astronotus ocellatus

The oscar, Astronotus ocellatus, is a large South American cichlid from slow rivers, floodplains, and forested waters of the Amazon basin and nearby drainages. Aquarium strains include tiger, red, albino, lutino, and long-finned forms, but all share the same heavy body, broad head, and interactive behavior. Oscars often recognize feeding routines and people near the tank, which is part of their appeal, but they are also territorial predators that grow far beyond small community-fish size.

Practical care starts with space and filtration. Adult oscars need large aquariums, strong biological filtration, regular water changes, secure lids, and tankmates chosen for size and temperament rather than novelty. They dig, move decor, produce heavy waste, and may eat smaller fish. Breeding pairs clean flat surfaces and guard eggs and fry aggressively. Unwanted oscars should be rehomed through aquarists or shops, never released, because large aquarium fish can harm local waterways.