Least Rasbora

🔥 Least Rasbora (Boraras urophthalmoides)

Add ultra-delicate movement and subtle colour to your aquarium with the charming Least Rasbora. One of the smallest aquarium fish in the world, this species features a soft translucent body with gentle reddish-orange tones and a distinctive dark spot near the tail.

Perfect for nano and heavily planted aquascapes, Least Rasboras bring peaceful, almost “floating ember” movement to the aquarium without overwhelming the layout.

🌿 Why Choose Least Rasbora?

🟠 Tiny nano schooling fish with soft orange hues
🐠 Extremely peaceful and gentle temperament
🌱 Perfect for nano, planted, and aquascaped tanks
✨ Subtle natural beauty rather than bold colour
⭐ Ideal micro fish for advanced nano setups in the UK

When kept in groups, Least Rasboras form tight, delicate shoals that drift slowly through plants, creating a calming and natural effect.

📏 Care Requirements

🧬 Scientific Name: Boraras urophthalmoides
📛 Common Name: Least Rasbora
🏠 Tank Size: 20L+ (nano suitable)
🌡️ Temperature: 24–28°C
⚗️ pH Range: 5.0–7.0
🧘 Temperament: Very peaceful
🍽️ Diet: Micro foods, baby brine shrimp, daphnia, crushed flakes
👥 Group Size: 10+ recommended

Least Rasboras thrive in mature, heavily planted aquariums with soft lighting, fine-leaved plants, and stable, soft water conditions.

🐠 Compatibility

Best suited for nano community aquariums with other micro species such as Chili Rasboras, Pygmy Corydoras, shrimp, and snails. Avoid larger or fast-moving fish that may outcompete them for food.

Important Notes

Due to their extremely small size, Least Rasboras require careful feeding and stable tank conditions. They are best suited to established aquariums and do best in larger groups where they feel secure and display natural schooling behaviour.

The Least Rasbora is an excellent choice for UK aquarists looking for one of the smallest, most delicate schooling fish available—perfect for natural nano aquascapes with subtle, elegant movement.