Epalzeorhynchos frenatum — Rainbow Shark
Family: Cyprinidae
Origin: Mekong, Chao Phraya, and other river basins of Southeast Asia
Size: 15–20 cm (6–8 inches)
Lifespan: 5–8 years
 
Natural Habitat
Environment: Freshwater rivers, streams, and floodplains with sandy or muddy substrates and dense vegetation
Water Conditions: Clear, oxygen-rich water with moderate flow
Temperature Range: 22–28°C (72–82°F)
 
Physical Description
Body Shape: Sleek, elongated body with a pointed snout
Coloration: Dark gray to black body contrasted by vivid red or orange fins
Fins: All fins brightly colored, especially striking against the darker body
 
Aquarium Care
Tank Size: Minimum 55 gallons; requires a long tank with swimming space
Water Parameters:
pH: 6.5–7.5
Temperature: 22–28°C (72–82°F)
Water Flow: Moderate
Substrate: Sand or fine gravel preferred
Décor: Caves, driftwood, and dense planting to create hiding spots and define territories
Filtration: Strong filtration with regular water changes
 
Diet
Type: Omnivorous
Preferred Foods: High-quality sinking pellets, algae wafers, live or frozen foods (bloodworms, daphnia), and vegetable matter (spinach, peas)
Feeding Frequency: Once or twice daily
 
Behavior & Tank Mates
Temperament:
Semi-aggressive, especially toward similar-shaped fish
Territorial as it matures
Compatible Tank Mates:
Fast, robust fish (Barbs, Rainbowfish, Loaches)
Avoid other bottom dwellers or similar-looking species
Behavior Notes:
Best kept singly unless in a very large tank to reduce territorial aggression
 
Breeding
Spawning Method: Egg scatterer (rarely breeds in home aquariums)
Breeding Conditions:
Complex and typically only successful in large, commercial breeding facilities
Fry Care:
Not commonly available through home breeding