Threadfin Rainbows (Iriatherina werneri) are small fish, usually around 4–5 cm, but males display exceptionally long thread-like dorsal and anal fins that flutter beautifully as they swim. Their bodies have a soft metallic sheen with hints of gold, silver, or blue depending on lighting.
They thrive in groups of 6 or more, especially with a higher ratio of females to males to reduce stress. These fish prefer tanks with dense plants, calm water flow, and clean, warm conditions.
Their gentle nature makes them excellent community fish with shrimp, rasboras, micro-rainbows, ember tetras, and similar peaceful species. Feeding is easy—micro pellets, crushed flakes, daphnia, baby brine shrimp, and fine frozen foods.
Why have them
Male Threadfin Rainbowfish are incredibly elegant, with long flowing fin extensions and shimmering colours that make them look like tiny underwater butterflies. They’re peaceful, active, and stunning in planted or nano community tanks—perfect for hobbyists who want something unique.


















