Red Fin Flagtail Fish (Semaprochilodus taeniurus) The Red Fin Flagtail is a stunning and active freshwater species, instantly recognisable by its bold silver body, striking vertical black stripes, and bright red/orange fins. Originating from the fast-flowing rivers of South America, this shoaling fish is a real showpiece, adding constant movement and colour to any large aquarium. Growing up to 8–10 inches (20–25 cm), the Red Fin Flagtail requires a spacious tank of at least 300 litres and is best kept in groups of 5 or more, where their natural shoaling behaviour shines. On their own, they may become shy, but in numbers, they are confident, energetic, and display their best colours. 🌊 Behaviour & Temperament: Active midwater swimmers that bring life to the aquarium. Generally peaceful but may be territorial in smaller groups. Best kept with larger, peaceful community fish (avoid very small tankmates). 🍴 Diet:Primarily herbivorous, the Red Fin Flagtail feeds on algae, plant matter, and biofilm in the wild. In the aquarium, they thrive on a diet of spirulina-based flakes, algae wafers, blanched vegetables (spinach, courgette, peas), along with some high-quality pellets and occasional frozen foods for variety. ⚡ Key Information: Scientific Name: Semaprochilodus taeniurus Common Name: Red Fin Flagtail, Red Finned Prochilodus Adult Size: 13-14 inches Tank Size: 400L minimum (larger for shoals) Temperature: 24–28°C pH: 6.0–7.5 Compatibility: Ideal with large peaceful species (e.g., Severums, Silver Dollars, Geophagus, larger Tetras) Lifespan: Up to 10 years with proper care The Red Fin Flagtail is a hardy, long-lived species that thrives in well-oxygenated tanks with open swimming space and strong filtration. With their shimmering silver scales and fiery fins, they make a breathtaking centrepiece in any large aquarium.
