Red Harlequin Rasbora - L

Species Profile

• Scientific Name: Trigonostigma espei
• Common Name: Red Harlequin Rasbora
• Adult Size: 2.5 to 3.5 cm (1 to 1.4 inches)
• Life Expectancy: 5 to 6 years with proper care
• Habitat: Slow-moving, shaded forest streams and peat swamps in Southeast Asia, particularly in Thailand and Cambodia. These environments are typically rich in tannins from decaying plant material and have soft, acidic water.

Tank Requirements

• Minimum Tank Size: 10 gallons (for a small school of 6–8 fish)
• Ideal Temperature: 22–28°C (72–82°F)
• pH Range: 5.0–7.0
• Water Hardness: 1–10 dGH (soft water preferred)
• Temperament: Peaceful, social, and best kept in groups of 6 or more. Ideal for community tanks with other non-aggressive species.

Diet & Nutrition

• Omnivorous: Yes. Will accept a wide range of foods, including:
  • High-quality flake or micro-pellets
  • Live foods (e.g., daphnia, brine shrimp)
  • Frozen foods (e.g., bloodworms)
  • Vegetable matter, like blanched spinach or spirulina flakes

Appearance

• Body Color: Reddish-orange body with a prominent black triangular patch extending from mid-body to the base of the tail
• Size: Small and slender with a slightly compressed body
• Fins: Often translucent with a hint of reddish-orange coloration, especially in healthy, well-fed specimens

Distinctive Features

• Triangular black marking on the posterior half of the body (more elongated than in other Trigonostigma species)
• More intense red coloration compared to the closely related Harlequin Rasbora (Trigonostigma heteromorpha)
• Highly active schooling behavior and striking contrast make them popular in planted aquariums