Oscars are native to the Amazon River and its surrounding areas, including Brazil, Colombia, Ecuador, French Guiana, and Peru. The Amazon River basin is one of the most biodiverse regions in the world.

Personality and Behavior:
Oscars are highly territorial and can display aggressive behavior, especially towards other fish that encroach on their space. This aggression is heightened during mating and feeding times. While they spend most of their time swimming in the middle levels of the tank, they often search the substrate for food, which may lead them to uproot plants and decorations. To prevent this, ensure that all tank decorations are secured.

Tank Mates:
Choosing the right tank mates is crucial as Oscars are known to attack other fish. They can typically be kept with other Oscars, especially when they have sufficient space to reduce territorial disputes. However, the key to keeping Oscars with other fish is providing a large enough tank and managing their space needs.

Size and Growth:
Oscars grow quickly and can reach up to 12 inches (30 cm) in size. They require ample space to avoid territorial conflicts, so a large tank is essential.

Diet and Feeding:
Oscars are omnivores and have a varied diet. In the wild, they primarily feed on small fish, larvae, insects, and crustaceans, but in an aquarium, they can be fed:

• Flake or pellet foods, designed for cichlids.
• Live or frozen foods, like bloodworms, brine shrimp, and daphnia, which encourage their natural hunting instincts.
• Though they may nibble on plants, this is not a significant part of their diet if they’re properly fed with other foods.

Tank Setup and Care:
Oscars require more maintenance than many other fish due to their large size and messy eating habits. Regular cleaning is vital to maintain water quality. Perform 20-25% water changes at least once a week, ideally twice, to prevent water conditions from deteriorating.

Health:
Oscars are hardy fish but can still become ill. They are less prone to disease than many other species but require attention to water quality and diet to avoid health issues.

Key Care Tips:

• Tank Size: Large, with plenty of space (minimum 75 gallons).
• Water Changes: 20-25% weekly, or more if necessary.
• Diet: Omnivorous, with a focus on live/frozen foods for protein and variety.
• Tank Mates: Can be kept with other Oscars or similarly sized robust fish in a large, well-maintained tank. Avoid overcrowding to minimize aggression.