Medaka Ricefish (Oryzias latipes) Care Guide

A tiny, elegant Japanese fish that has surged in popularity worldwide. Extremely hardy and cold-tolerant, it thrives in outdoor tubs and indoor nano tanks alike.

Overview

Oryzias latipes is a species in the family Adrianichthyidae. A tiny, elegant Japanese fish that has surged in popularity worldwide. Extremely hardy and cold-tolerant, it thrives in outdoor tubs and indoor nano tanks alike. Available in many selectively bred color varieties including orange, platinum, and blue. One of the few fish comfortable in both cool and warm water.

Taxonomy

Family: Adrianichthyidae
Genus: Oryzias
Scientific name: Oryzias latipes
Other names: Japanese Ricefish, Japanese Killifish, Oryzias
Origin: East Asia, Japan, Korea, China

Habitat

Native to East Asia including Japan, Korea, China and Vietnam. Inhabits still and slow-moving fresh and brackish waters such as rice paddies, ditches and ponds. Highly tolerant of temperature and salinity fluctuations; a long-established model organism in biology.

Tank requirements

Minimum tank volume: 20 L
Temperature: 4-30 °C
pH: 6.5-8
GH: 5-20 °dGH
Water flow: low
Adult size: 3-4 cm
Lifespan: 2-4 years
Recommended group size: ≥ 6
Difficulty: beginner

Diet

Classified as omnivore. Recommended feeding frequency: 2x daily. In captivity, offer a varied diet appropriate to the species — quality prepared foods supplemented with frozen or live items of suitable size.

Compatibility

Temperament: peaceful
Swimming level: top
Compatible tank mates: Cherry Shrimp, Nerite Snail, White Cloud Minnow, Corydoras
Avoid with: Large Fish, Aggressive Fish, Betta

Breeding

Breeding strategy: egg-depositor
Breeding difficulty: beginner