The rice fish, also known as the Japanese medaka, is scientifically called Oryzias latipes.

These small freshwater fish are slender, semi-transparent, and shimmer with silver, pale gold, or pearly tones. They usually grow to about 1–1.5 inches (2.5–4 cm) long. Their delicate fins and large round eyes give them a soft, almost glass-like appearance.

Originally native to Japan, Korea, and parts of China, rice fish earned their name because they were often found swimming in flooded rice paddies.

CARE INSTRUCTIONS:

Tank Size

• Minimum 5 gallons for a small group

• They do best in groups of 4–6 or more (peaceful schooling fish)

Water Parameters

• Temperature: 65–78°F (18–26°C)

• pH: 6.5–8.0

• They are hardy and tolerate a wide range of conditions

• Gentle filtration preferred (low flow)

Tank Setup

• Planted tank recommended

• Floating plants are ideal

• Lid required (they can jump!)
  
  

Rice fish are omnivores and not picky.

Staple Foods:

• High-quality micro pellets

• Crushed tropical flakes

Protein Treats (great for color and breeding):

• Baby brine shrimp

• Daphnia

• Bloodworms (frozen or live)

• Mosquito larvae

Feed small amounts 1–2 times daily — only what they can finish in a few minutes.

Fun Facts

• Rice fish are one of the first vertebrates to go to space for breeding experiments.

• They are used in scientific research because their embryos are transparent.

• They can tolerate both freshwater and slightly brackish water.

• Some strains glow under certain lighting due to selective breeding.

• They’ve been kept in Japan for over 300 years.