Oscar
Astronotus ocellatus
Cichlidae
About
The Oscar is a large, intelligent cichlid from the slow, warm waters of the western Amazon and Orinoco basins, where it hunts among mud- and sand-bottomed pools and flooded margins. Reaching 30-38 cm and living well over a decade, it is a heavy-bodied predator that swallows any fish small enough to fit its wide mouth, and it constantly digs, uproots plants and rearranges its surroundings. Its personality and habit of recognising its keeper make it a hobby favourite, but it is very commonly mis-kept and quickly outgrows undersized tanks.
Care
Give a single Oscar (or a bonded pair) a large, long tank with a base of at least 150 cm (about 450 L) with powerful, over-rated filtration and weekly 30-50% water changes to handle its huge bioload. Use a secure lid, sand substrate and robust decor. House only with similarly large, non-bite-sized tankmates.
Diet
Predatory omnivore that eats fish, crustaceans and insects in the wild. Staple on a quality cichlid pellet plus earthworms, prawns, mussel and whitefish; skip feeder fish and mammal meat, and control portions to protect water quality.
Tankmate compatibility
Avoid (121)
Computed by the AquaSage engine for a spacious reference tank — always check the full verdict for your exact setup in the calculator.