Neon Blue Axelrodi Rasbora (Sundadanio Axelrodi var. "Blue")

Neon Blue Axelrodi Rasbora (Sundadanio axelrodi var. “Blue”) — Electric Colour for the Nano Aquarium

The Neon Blue Axelrodi Rasbora (Sundadanio axelrodi var. “Blue”) is one of the most intensely coloured nano fish in the freshwater hobby. This diminutive gem from the blackwater streams of Borneo and Sumatra blazes with an almost surreal electric blue iridescence — a colour so vivid it seems to glow from within, especially under low or warm aquarium lighting. In a school, the effect is mesmerising.

A Jewel That Glows

At just 1.5–2 cm in length, the Neon Blue Axelrodi Rasbora punches far above its weight in visual impact. A school of 15 or more moving through a heavily planted nano aquarium creates a shimmering, electric-blue cloud that rivals any fish in the hobby. Their constant, darting movement and intense colouration make them endlessly captivating — a living light show in miniature.

Care Profile

• Scientific Name: Sundadanio axelrodi var. “Blue”
• Origin: Borneo and Sumatra — soft, acidic blackwater streams and peat swamps
• Size: Up to 1.5–2 cm
• Temperament: Peaceful; best kept in schools of 15 or more for natural schooling behaviour and reduced stress
• Diet: Micro-predator — accepts micro pellets, baby brine shrimp, micro worms, and finely crushed flake food
• Water Temperature: 22–28°C
• pH: 4.0–6.5 (thrives in soft, acidic, tannin-rich water; colour is most vivid in blackwater conditions)
• Tank Size: Suitable from 20L upward; ideal for nano tanks of 30–60L
• Note: Due to their tiny size, avoid keeping with any fish large enough to eat them — best kept as a species tank or with other nano fish and dwarf shrimp

Aquascape Compatibility

Plant-safe and an excellent companion for dwarf shrimp such as Neocaridina and Caridina species. The Neon Blue Axelrodi Rasbora thrives in heavily planted nano aquariums with dark substrates, driftwood, Indian almond leaves, and soft, acidic water that replicates its Sundaic blackwater habitat. Their electric blue colouration is most vivid and intense in these conditions, creating a spectacular contrast against lush green planting.

Tiny, electric, and utterly breathtaking — the Neon Blue Axelrodi Rasbora is the nano fish that turns any planted aquarium into a living light show.