Rainbow – Werneri Threadfin Rainbowfish – 4cm

Werneri Threadfin Rainbow (Iriatherina werneri): A Graceful and Unique Aquarium Addition

The Werneri Threadfin Rainbow (Iriatherina werneri) is a stunning freshwater fish admired for its delicate fins and shimmering colours. Native to Australia and Papua New Guinea, this fish is a favourite for aquarists seeking elegance. Its peaceful temperament makes it ideal for well-planted community tanks, where it brings life and beauty.

Tank Setup for Werneri Threadfin Rainbow

Creating the right environment is crucial for their well-being. A 50-liter tank is suitable for a small group, but larger tanks provide better swimming space. Use fine sand or gravel and include plenty of live plants for shelter. Floating plants help diffuse light, which these fish prefer. Maintain water temperatures between 24°C and 28°C and a pH range of 6.0 to 7.5. Regular water changes keep conditions stable and healthy.

Diet and Feeding

Threadfin Rainbows thrive on a diet tailored to their small mouths. Provide high-quality micro-pellets as a staple. Supplement this with live or frozen foods like daphnia, baby brine shrimp, and microworms. Feeding smaller portions more frequently ensures they can eat comfortably. A varied diet rich in protein supports their vibrant colours, energetic swimming, and overall health.

Behaviour and Tank Mates

These fish are peaceful and do well with similarly gentle tank mates. Suitable companions include small tetras, rasboras, and dwarf corydoras. Avoid larger or aggressive species that might outcompete them or damage their delicate fins. Keeping at least six Threadfin Rainbows encourages natural shoaling behaviour, adding dynamic movement to your tank. A well-thought-out community enhances their peaceful interactions.

Breeding Werneri Threadfin Rainbow

Breeding these fish is possible with proper care. Males display vibrant fins and colours to attract females. To encourage spawning, set up a separate tank with soft water and fine-leaved plants or spawning mops. Females scatter eggs, which hatch in 7–10 days. Feed the fry infusoria or finely crushed flakes until they grow large enough for other foods. Stable water conditions are essential for success.

FAQs

How big do Werneri Threadfin Rainbows grow?
They grow up to 4–5 cm, making them perfect for nano and medium-sized tanks.

Are they aggressive?
No, they are peaceful and thrive with other non-aggressive species.

What tank mates are suitable?
Good companions include small tetras, rasboras, and bottom-dwellers like dwarf corydoras.

What do they eat?
They enjoy micro-pellets, live foods such as daphnia, and frozen baby brine shrimp.

How do they breed?
Females scatter eggs among plants. Stable water and soft lighting encourage spawning.

Are they beginner-friendly?
They are best for intermediate aquarists due to their delicate nature and specific feeding needs.

Species Overview

• Species: Iriatherina werneri
• Common Name: Werneri Threadfin Rainbow
• Origin: Australia, Papua New Guinea
• Diet: Omnivore
• PH Range: 6.0–7.5
• Temperature: 24°C–28°C
• Max Size: Up to 5 cm
• Tank Size: Minimum 50 liters