Red Tailed Black Shark
Red Tailed Black Shark
Red Tailed Black Shark (Epalzeorhynchos bicolor) is one of the most iconic aquarium fish ever developed — the pure matte-black body contrasting with a vivid scarlet caudal fin is a combination so striking it has made this fish a hobby staple for decades. It is also one of the most important conservation stories in the hobby: this species is IUCN Critically Endangered and is believed to be extinct in its native wild habitat in the Chao Phraya River basin of central Thailand.
Feeding & Care Tip: Hikari Mini Algae Wafers and Sera Vipan Tropical Flakes make excellent daily staples. Supplement with Hikari Frozen or Freeze-Dried Bloodworms and Hikari Frozen or Freeze-Dried Tubifex Worms 2–3 times per week. Feeds primarily at the substrate level.
Historically native to the Chao Phraya River drainage in central Thailand. The species was once common in the Mae Klong and Chao Phraya rivers but was last recorded in the wild in 2011. Habitat destruction, dam construction, and agricultural pollution are believed to have eliminated the wild population. Every Red Tailed Black Shark in the aquarium hobby is captive-bred — the species exists today almost entirely because of aquarium keeping.
Like the Rainbow Shark, one per tank — territorial toward conspecifics and similarly shaped fish. The territorial behavior is significant in smaller tanks; in larger aquariums (150+ gallons) with extensive hardscape, multiple individuals have been kept successfully. Compatible with fast-moving species that occupy different tank zones.
The Red Tailed Black Shark is a remarkable case of a species sustained by the aquarium hobby after disappearing from the wild. Every captive-bred fish represents the continuation of a species that no longer exists in nature. The combination of conservation significance and extraordinary visual impact makes this one of the most meaningful fish in the hobby.
Care & Ideal Parameters
| Difficulty | Easy — Moderate |
| Temperament | Territorial — one per tank |
| Typical Adult Size | 6.0 inches (15 cm) |
| Min. Group Size | One per tank only |
| Ideal Temp | 72–82°F (22–28°C) |
| Ideal pH | 6.5–7.5 |
| Ideal GH | 5–15 dGH |
| Ideal KH | 2–8 dKH |
| Staple Food | Hikari Mini Algae Wafers; Sera Vipan Tropical Flakes |
| Treat / Supplement | Hikari Frozen or Freeze-Dried Bloodworms; Hikari Frozen or Freeze-Dried Tubifex Worms |
| Origin | Chao Phraya River basin, central Thailand (IUCN Critically Endangered — believed extinct in wild) |
| Notes | IUCN Critically Endangered — believed extinct in wild since ~2011. Chao Phraya River, Thailand. All stock captive-bred. Species sustained entirely by aquarium hobby. Pure black body + scarlet tail. Territorial — one per tank. |
