Medaka

Oryzias latipes

Medaka (Oryzias latipes) — Varies care, Peaceful, under Other. Minimum tank in the app: 9.2 US gal min; aim for 61–72°F and pH 6.5–7.5. Medaka, or Oryzias latipes, is a versatile species that appeals to aquarists seeking adaptable fish with unique behaviors.

Medaka (Oryzias latipes) in a planted freshwater aquarium
Care levelVaries
TemperamentPeaceful
Min tank size9.2 US gal min
pH range6.5–7.5
Temperature61–72°F
Max size1.4 in (3.5 cm)
Captive lifespan2–4 years
SchoolingNo

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.

Natural distribution

Asia

  • East & Southeast Asia

Regional colours match the stocking calculator’s origin map.

Medaka Tank Setup

A 35L tank should balance open swimming space with plenty of hiding spots, such as plants and driftwood, to accommodate their mid-water swimming habits. A gentle current and moderate lighting can enhance their activity levels while keeping them comfortable. Use a fine substrate to minimize stress during foraging, as they often explore the tank floor for food.

What Do Medakas Eat?

Medaka are omnivorous and typically feed at a moderate pace, which can lead to competition if housed with faster or more voracious feeders. Providing a varied diet enhances their health and coloration, but it's essential to ensure all fish can access food to prevent stress and health issues.

Medaka Tank Mates

Ideal companions include similarly sized, moderately active species that occupy different tank zones, such as small tetras or rasboras; avoid overly large or aggressive fish that could intimidate them. Intraspecies interactions can vary; while they don't shoal, providing multiple territories can help mitigate aggression, especially among males during breeding periods.

Are Medakas Good for Beginners?

Care demand varies with setup and individual fish; use the numbers above as your baseline. Aquarists often underestimate the importance of environmental complexity for Medaka, leading to stress and aggression in poorly structured tanks. neglecting water parameters can result in health issues, as they thrive within specific pH and temperature ranges.

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