Quick Stats: Oscar
Scientific Name: Astronotus ocellatus
Origin: the South American Amazon Basin, French Guyana and Suriname.
Max Size: 12 inches
Temperament: Oscars are also called “river dog” or “water dog” because of the way they interact with their owners. They shake their tail and head just like dogs do, which is the reason people fall quickly in love with them. They like to “redecorate” their aquarium by moving things around and excavating the substrate, so it’s easier to leave it like it is. They also seem to “play” with objects placed around their tank and can even be trained to knock balls into small nets or swim through loops. They can actually get to know their owners and even eat from their hand.
Description: Oscars are usually dark colored, with yellow spots (ocelli, these giving them the scientific name of Astronotus ocellatus). Young Oscars have different coloration than the adults; they have white and orange stripes and spotted heads. Due to interbreeding wild specimens throughout time, there are now many types of Oscar cichlids besides the original, wild ones:
Behavior: Oscars will often lay claim to an area of the aquarium and will be very aggressive towards other fish encroaching on their newly established territory. The size of the territory varies depending on the size and aggressiveness of the fish based on its surroundings. Once the oscar establishes a territory, it will vigorously defend it by chasing away other fish.
Tank Region: Oscars capture and claim areas of the aquarium and will show aggression if other fish encroach their established territory. They like to live alone in their defined territory and do not like to live in community.
Compatibility : When provided with plenty of open swimming areas, rocks and crevices, it is not usually aggressive toward tank mates. Should not be kept with smaller fish.
Experience Level: Medium
Diet: Oscars eat a wide variety of foods consisting of a balance between live foods and processed ones. Before choosing any food for your velvet cichlids, make sure it is no bigger than its mouth.
Temperature: 77F-80F / 23C-26C
Tank Setup: Driftwood, Roots, Caves, and Rocks with wide open spaces for swimming. They will decimate live plants, so stick to the artificial ones if you wish to decorate, keeping in mind that it will all be moved. In the wild, they will often jump out of the water to catch insects from overhanging leaves and branches. This behavior is mimicked in the aquarium, so make sure it has a tight-fitting cover. Oscars. Good filtration is a must, as Oscars are messy. They produce a lot of waste. They stir up the gravel when they eat and when they rearrange their furniture.
Fun fact: Oscars use a suction mechanism to capture prey, and have been reported to exhibit "laying-on-side" death mimicry