Saltwater Aquarist

Rainbow Shark

(Epalzeorhynchos frenatum)

Rainbow Shark (Epalzeorhynchos frenatum) in a freshwater aquarium

Species Description…

Scientific Name: Epalzeorhynchos frenatum
Common Name: Rainbow Shark
Species Group: Cyprinid
Tank Type:
Care Level: Intermediate
Temperament: Semi-aggressive
Diet Type: Omnivore
Role in Aquarium: Bottom Dweller
Max Fish Length: 6 (inches)
Min Aquarium Size: 44 (gallons)
Native Range: Thailand, Laos and Cambodia (Mae Klong, Chao Phraya and Mekong basins).
Min Temperature: 68°F
Max Temperature: 79°F
Min pH: 6.5
Max pH: 8
Min GH: 2 dGH
Max GH: 15 dGH
Min Group Size:
Breeding: Difficult
Lifespan: years

Overview

  • The Rainbow Shark (Epalzeorhynchos frenatum) is a dark-bodied cyprinid with red fins. An albino form is common.
  • Reportedly native to Thailand, Laos and Cambodia, in the Mae Klong, Chao Phraya and Mekong basins.
  • Grows to about 6 in (15 cm) standard length.

Feeding

  • Grazes algae and small invertebrates.
  • Offer quality dried foods plus regular small live and frozen foods for the best color.

Habitat

  • A tank with a base of 48 × 18 in (120 × 45 cm).
  • Plenty of cover. A river-style setup with rocks and wood suits it.
  • Water: 68–79°F (20–26°C), pH 6.5–8.0, GH 2–15.

Fish Care

  • Usually won’t harm soft-leaved plants.

Compatibility

  • A slightly better community fish than the red-tailed black shark, but choose tankmates carefully.
  • Very aggressive toward similar-looking fish. Keep only one per tank unless the tank is very large. [UNVERIFIED]

Aquarium Behavior

  • Juveniles hide a lot, but become more territorial as they grow.

Breeding

  • Not bred in home aquariums.
  • Farmed in large numbers for the trade using hormones.