Ulysses Medaka Ricefish (Oryzias latipes)

*Note : Photos are of the breeding group, actual fish may vary individually.

Ulysses Medaka Ricefish (Oryzias latipes – Ulysses Variety)

Bold, vivid, and unlike any other medaka — the Ulysses Medaka is a striking Japanese ricefish variety that commands attention with its rich, deep colouration and distinctive patterning. Named after the legendary voyager, this medaka is a true explorer's fish: rare, sought-after, and endlessly fascinating to observe. Whether kept in a planted aquarium or an outdoor tub, the Ulysses Medaka brings a sense of adventure and colour to any setup.

Fish Details

• Adult Size: 3–4 cm (1–1.5 inches)
• Temperament: Peaceful, active schooling fish
• Diet: Omnivore — accepts high-quality flake food, micro pellets, and small live/frozen foods (baby brine shrimp, daphnia, micro worms)
• Lifespan: 2–4 years
• Breeding: Egg layer — females carry egg clusters and deposit them on plants or spawning mops; eggs hatch in 10–14 days

Tank Requirements

• Minimum Tank Size: 40 L (10 gallons)
• Water Temperature: 18–26°C (64–79°F) — adaptable; tolerates cooler temperatures well
• pH: 7.0–8.0
• Water Hardness: Moderately hard to hard
• Lighting: Moderate to bright — brings out the full depth of their colouration

Compatibility

• Best kept in groups of 6 or more for natural schooling behaviour and reduced stress
• Ideal tankmates: other medaka varieties, small rasboras, corydoras, snails, and freshwater shrimp
• Avoid housing with large or fin-nipping fish
• Can be kept in outdoor tubs or ponds during warmer Canadian months

Care Tips

• A dark substrate enhances their colouration beautifully
• Floating plants like water lettuce or frogbit provide shade and mimic their natural rice paddy habitat
• Easy to breed — add a spawning mop or fine-leaved plants and they will readily spawn
• Perform regular water changes of 20–30% weekly to maintain optimal health and vibrancy
• Keep the tank covered — medaka are known to jump

Rare, vibrant, and full of character — the Ulysses Medaka Ricefish is a collector's gem that brings bold colour and lively energy to any aquarium or pond.