Black Nemo Oscar Care Guide

Astronotus ocellatus

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Bioload Score

14000

Semi-AggressiveModerate
Max Size
45 cm / 18"
Temperature
23–27°C (74–81°F)
pH Range
6 – 8
Min Tank Size
280L (74 gal)
Min Group Size
Can be kept alone
Tank Level
Mid-Top
Origin
South America
Temperament
Semi-Aggressive
Difficulty
Moderate
Breeding Difficulty
Moderate

Diet

An omnivorous predator that eats insects, crustaceans, small fish, worms and plant matter.

Community Compatibility

Suitable tankmates include large robust South American cichlids, large catfish, silver dollars and other similarly sized fish that are not timid or fin-nipping.

Good to Know

The Black Nemo Oscar is a selectively bred colour form of Astronotus ocellatus, a cichlid famous for recognising its keeper and begging for food.

Gender Differences

Males and females are difficult to distinguish outside breeding, although mature males may be slightly larger and females develop a more prominent ovipositor when spawning.

About the Black Nemo Oscar

The Black Nemo Oscar is a selectively bred colour variety of the Oscar, Astronotus ocellatus, displaying dark black and charcoal tones often contrasted by orange, red or mottled markings. Like other Oscars, it has a deep-bodied shape, large expressive eyes and a powerful mouth suited to its predatory lifestyle.This variety has the same imposing personality as the wild species and is known for its intelligence and individual character. Oscars often learn to recognise people, follow activity outside the aquarium and interact with objects in their surroundings, making them unusually engaging among large freshwater fish.In nature, Astronotus ocellatus inhabits slow-moving rivers, floodplain lakes and seasonally flooded forests across tropical South America, particularly within the Amazon and Orinoco drainage systems. Its natural environment is typically warm, soft to moderately mineralised and structurally varied, with submerged roots, branches and leaf litter.The species was formally described by the French naturalist Louis Agassiz in 1831. Wild Oscars are commonly brownish or grey with orange markings and characteristic eyespots, while aquarium strains such as Black Nemo have been developed through selective breeding for distinctive colour patterns.Oscars are powerful, long-lived cichlids with strong territorial instincts and a talent for rearranging their surroundings. Their large adult size and assertive behaviour have made them one of the best-known showcase fish in freshwater aquaria.

Stock Black Nemo Oscar in Your Tank

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