Bengal glass danio

Danionella priapus

Also known as Glass micro danio, Vampire danio

FreshwaterFish

Bengal glass danio (Danionella priapus) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 72–79°F (22–26°C)
pH: 6.0–7.5
Adult size: 0.7 in (1.9 cm)
Minimum tank: 5 gal (20 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: Medium
Rarity: Rare
Origin: Streams of northern West Bengal, India
Family: Danionidae

Overview

This is one of the smallest fish in the hobby, a see-through midwater schooler that needs a quiet nano tank and no boisterous company. Keep at least a dozen together, since the group hangs in loose formation and single fish are almost impossible to observe. Because it is tiny and delicate, its only tankmates should be equally small, gentle species, or none at all. Feed the smallest foods: microworm, baby brine shrimp, cyclops, and finely powdered dry food. A mature, gently filtered tank of around 20 liters is enough.

In the wild

The Bengal glass danio comes from shallow, gently flowing streams in northern West Bengal, India, among fine plants and soft substrate. A small, mature tank suits its scale, with fine-leaved planting, gentle filtration, a soft dark substrate, and dim light to bring out what little color it has. Keep it at 22 to 26 degrees Celsius with a pH of 6.0 to 7.5.

Good to know

Danionella priapus is a miniature member of the danio family, Danionidae, maturing at under 2 centimeters and staying transparent and scaleless for life. Britz described it in 2009. The genus Danionella has become important in neuroscience because its transparency lets researchers watch living brain activity through the intact body. Spawning is possible but takes stable, mature water, so its breeding rates as moderately tricky.

Did you know

Members of this genus are so clear that scientists can image a living fish's brain firing through its own skin, which has turned a fish under two centimeters long into a laboratory window on the vertebrate brain.