Red Oscar

Species Profile

• Scientific Name: Astronotus ocellatus
• Common Name: Red Oscar
• Adult Size: 10–12 inches (25–30 cm), occasionally up to 14 inches in large tanks
• Life Expectancy: 10–15 years (with excellent care)
• Habitat: Native to slow-moving rivers, streams, and floodplains in the Amazon Basin (Brazil, Peru, Colombia); prefers warm, soft waters with submerged roots and debris

Tank Requirements

• Minimum Tank Size: 75 gallons for one adult; 100+ gallons for a pair or with tankmates
• Ideal Temperature: 74–81°F (23–27°C)
• pH Range: 6.0–8.0 (prefers slightly acidic to neutral)
• Water Hardness: 5–20 dGH
• Temperament: Intelligent, interactive, but territorial and aggressive, especially toward smaller fish; can be kept with other large, robust fish if space allows

Diet & Nutrition

• Omnivorous: Yes
  • Eats a variety of foods: high-quality cichlid pellets, live/frozen foods (earthworms, crickets, shrimp), and occasional vegetables (peas, spinach)
  • Enjoys treats like mealworms and feeder fish (sparingly and only from disease-free sources)
  • Requires a balanced, protein-rich diet to maintain growth and coloration

Appearance

• Deep-bodied and powerful, with a base color ranging from black to dark gray
• Bright red to orange patterns spread across the body, often in blotches or stripes
• Coloration varies by strain, age, and health; selective breeding has intensified red hues in Red Oscars
• Eyes often have a reddish ring and may "track" movement

Distinctive Features

• Known for their intelligence and owner recognition—can be trained to take food from hand
• Display “begging” behavior at the front of the tank when hungry or curious
• Prone to digging and redecorating their tank space
• Can develop HLLE (Hole-in-the-Head Disease) if water quality or diet is poor