Shoal & Stem
Back to Flora & Fauna

No photo yet

Sign in to submit the first photo

FishbeginnerFreshwater

Blue Medaka

Oryzias latipes

AnimaliaChordataActinopterygii

Variety of Medaka · blue

📍 Japan

Ask Finn

The Blue Medaka is a selectively bred color form displaying a soft blue iridescence. Like all medaka, it is extremely hardy, peaceful, and suitable for nano aquariums or outdoor tubs, thriving in groups.

Size1.5"
Min Tank10g
School6+
peaceful
Zonetop

Care Guide

Diet

Blue Medaka are omnivorous and accept high-quality flake foods, micro pellets, and small frozen foods like brine shrimp and daphnia. Feed small amounts once daily, only what they can consume in 2-3 minutes. They will also graze on algae and microorganisms in planted tanks.

Behavior

Blue Medaka are peaceful, schooling fish that thrive in groups of 6 or more and display their best coloration when kept together. They are active swimmers that prefer gentle water flow and spend most of their time in mid-water levels. They are hardy and adaptable, making them excellent for beginners and can tolerate a wide range of conditions.

Breeding

Blue Medaka breed readily in captivity with minimal intervention, making them ideal for hobbyists interested in selective breeding. Females lay adhesive eggs on plants or spawning mops daily once conditioned; eggs hatch in 7-10 days at 25-26°C. Separate fry to a nursery tank with infusoria or liquid fry food, as they are very small at birth.

Common Diseases

Ich (Ichthyophthirius multifiliis)

Symptoms

White spots on body and fins, flashing against objects, lethargy, rapid gill movement

Treatment

Raise temperature gradually to 28-30°C, perform daily 25% water changes, use aquarium salt (1 tsp per gallon) or ich medication for 7-10 days

Fin Rot

Symptoms

Frayed or deteriorating fins, discoloration at fin edges, lethargy

Treatment

Improve water quality with frequent partial water changes, reduce stocking density, treat with antibacterial medication if severe

Bacterial Infection

Symptoms

Ulcers, sores, cloudy eyes, loss of appetite, color fading

Treatment

Perform 50% water change immediately, maintain pristine water conditions, use broad-spectrum antibiotic medication as directed

Parasitic Infection

Symptoms

Excessive scratching, visible parasites, weight loss, clamped fins

Treatment

Quarantine affected fish, treat with anti-parasitic medication, maintain elevated temperature and perform frequent water changes

Community Photos

0 photos

Photos are added when members log a tank with this species and upload a photo in their tank journal. Add your own tank to contribute.

No photos yet — add a tank with Blue Medaka to be the first!

Sign in to vote.

Tips from the community 💡

0 tips

Real experiences, care advice, and keeper notes. Finn learns from these too.

Sign in to share your experience.

No community tips yet — be the first to share your knowledge!

Stats

Community tips0
Kept by0 hobbyists