Danionella cerebrum

Also known as Danionella translucida, Translucent danio, Glass danio

FreshwaterFish

Danionella cerebrum (Danionella cerebrum) — AngryBurmese · CC BY-SA 4.0

Care at a glance

Temperature: 72–82°F (22–28°C)
pH: 6.5–7.5
Adult size: 0.5 in (1.3 cm)
Minimum tank: 8 gal (30 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: Medium
Rarity: Rare
Origin: Native to shallow, slow streams and pools in the Bago region of southern Myanmar.
Family: Cyprinidae

Overview

Keep this fish in a group of at least ten in a mature, gently filtered tank of 30 litres or more at 22 to 28 C with a pH of 6.5 to 7.5. Its very small size means it can only take tiny foods such as baby brine shrimp, microworm, cyclops, and finely crushed flake. It is far too small for most tankmates and is best kept in a species-only nano tank or with dwarf shrimp. Stable water and low flow matter more than any exact number.

In the wild

Danionella cerebrum is a tiny, see-through fish from shallow, slow-moving and standing waters in southern Myanmar. Its body is almost fully transparent, so the spine and internal organs show through. It swims in loose groups in open midwater and is very sensitive to poor conditions. This is a specialist nano fish for a mature, stable tank.

Good to know

Described in 2021, Danionella cerebrum is the species behind most of the fish traded and studied under the older name Danionella translucida, which is a genuinely different fish. It matures at little more than a centimetre and keeps a larval-like body that never fully ossifies, leaving it transparent. Despite the size, males can produce clicks louder than 140 decibels by drumming a muscle against the swim bladder.

Did you know

Because you can see straight through it to the brain and spine, Danionella cerebrum has become a major laboratory model for studying how vertebrate brains work in a living, moving animal.