Dwarf Emerald Rasbora

Introduction

The Dwarf Emerald Rasbora is a tiny, peaceful freshwater fish known for its shimmering green body with striking vertical stripes and hints of orange. A favorite among nano aquarium enthusiasts, this fish is admired for both its beauty and its active schooling behavior.

Scientific Name

Microrasbora erythromicron

Common Name

• Dwarf Emerald Rasbora

• Emerald Dwarf Rasbora

Water Quality and Temperature

• Temperature: 20°C – 26°C (68°F – 79°F)

• pH: 6.5 – 7.5

• Hardness: 2 – 10 dGH

• Prefers clean, slightly soft water with stable conditions and gentle filtration

Feeding

• Omnivorous

• Accepts micro-sized flakes, pellets, and live or frozen foods such as:

  • Baby brine shrimp

  • Daphnia

  • Micro-worms

• Should be fed small amounts 2–3 times daily

Tank Mates

• Ideal for peaceful community tanks with other small species such as:

  • Chili Rasboras

  • Pygmy Corydoras

  • Celestial Pearl Danios

  • Shrimp and snails

• Avoid larger or aggressive fish that may see them as food

Substrates and Tank Decorations

• Fine dark sand or gravel to bring out their colors

• Dense planting with hiding places using:

  • Driftwood

  • Rocks

  • Leaf litter

• Low lighting helps enhance their iridescent coloration

Suitable Plants

• Java Moss

• Anubias Nana

• Cryptocoryne species

• Water Wisteria

• Floating plants like Salvinia or Frogbit

Sexing

• Males: More vibrant coloration, thinner bodies, and more intense striping

• Females: Slightly larger, rounder bellies and duller coloration

Breeding

• Egg scatterers; breeding occurs in dense vegetation

• Adults may eat the eggs, so use a breeding tank or dense planting

• Eggs hatch in 2–3 days; fry can be fed infusoria, followed by baby brine shrimp

Maximum Size and Longevity

• Size: Up to 2 cm (0.8 inches)

• Lifespan: 3 – 5 years with good care

General Information

The Dwarf Emerald Rasbora is perfect for nano aquariums and aquascaped tanks. Their shy yet active schooling behavior makes them best kept in groups of at least 6–8 to reduce stress and bring out natural behavior.

A Fun Fact

Despite their “rasbora” name, genetically they are more closely related to danios and were even reclassified under the Danio genus for a time!