Iriantherina warneri (Rainbow threadfin werneri)

Iriatherina werneri (Threadfin Rainbowfish)

Background:

The Threadfin Rainbowfish, Iriatherina werneri, is a delicate and exquisitely beautiful freshwater species native to the slow-moving rivers and swamps of New Guinea and northern Australia. This unique fish is known for its elongated, thread-like fins and elegant body, which shimmers in hues of silver, gold, and blue. Males, in particular, are adorned with long, flowing fins that they display in captivating courtship dances. Growing to about 4–5 cm in length, the Threadfin Rainbowfish is a peaceful and mesmerizing addition to planted or community aquariums, where it thrives in tranquil, well-maintained environments.

Care Requirements:

• Water Parameters:

  • Temperature: 23–28°C
  • pH: 6.0–7.5
  • Hardness: 5–12 dGH

• Diet:
  Threadfin Rainbowfish are micro-predators, thriving on a diet of live or frozen foods such as baby brine shrimp, daphnia, and cyclops. Supplement with finely crushed flakes or micro pellets designed for small fish. Feed them small portions 2–3 times daily to ensure consistent energy for their active lifestyle.

• Tank Setup:
  A minimum tank size of 40 liters is recommended for a group of 6 or more individuals. Provide a fine, dark substrate to highlight their colors and a densely planted tank with species like Java moss, Vallisneria, and floating plants to create shaded areas. Open swimming spaces are essential to allow for their graceful displays. A gentle water flow and subdued to moderate lighting enhance their natural elegance and behavior.

• Behavior:
  Threadfin Rainbowfish are peaceful and highly social, thriving in groups of at least 6. Males engage in elaborate fin displays, especially in the presence of females or during interactions with other males. These fish prefer the mid-to-upper water column and exhibit shy but active behaviors in a stress-free environment.

• Tank Mates:
  Ideal companions include small, peaceful species such as Ember Tetras, Neon Tetras, and Pygmy Corydoras. They also pair well with small shrimp like Cherry or Amano Shrimp. Avoid housing them with larger, aggressive, or fin-nipping species, as their delicate fins are easily damaged.

Care Tips:

Threadfin Rainbowfish are sensitive to water quality, so perform regular partial water changes and maintain stable parameters. Ensure a peaceful environment with ample plants and subdued lighting to reduce stress and encourage natural behaviors. Their diet should consist of small, easily digestible foods to accommodate their small mouths. Keep them in groups to promote social interactions and reduce shyness.

The Threadfin Rainbowfish is a dazzling and graceful species that adds sophistication to any peaceful aquarium. Its shimmering colors, intricate fins, and captivating courtship displays make it a prized choice for aquarists seeking a unique and elegant addition to their tanks.