Threadfin Rainbowfish

Threadfin Rainbowfish (Iriatherina werneri) is a delicate and graceful species native to slow-moving rivers, swamps, and floodplains of northern Australia and New Guinea. It is instantly recognizable by its long, flowing fins and shimmering silver body with subtle yellow and red highlights, making it a standout in planted aquariums.

Key Care Points:

• Behavior & Swimming: Peaceful, kinda, and best kept in groups of 6 or more. Males display their long thread-like fins while sparring harmlessly, These fish glide gracefully in the mid-to-upper levels of the tank.

• Tank Requirements: Calm water flow. Prefers dense planting along with open swimming space.

• Diet: Omnivorous. Accepts quality flakes and micro-pellets.

• Lifespan: Typically 3–5 years with good care.

• Max Size: Up to 2 inches (5 cm).

• Growth Rate: Slow; juveniles take several months to show their flowing fin extensions and full coloration. The ones we sell may not have yet fully developed.

The Threadfin Rainbowfish’s elegant fins and gentle schooling nature make it an excellent choice for peaceful community and planted aquariums.