TankBud

Bernatzik's baril

Opsarius bernatziki

Also known as Barilius bernatziki, Blue hillstream trout

FreshwaterFish

Bernatzik's baril (Opsarius bernatziki)
The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature
72–81°F
22–27°C
pH
6.5–7.5
Adult size
4.3 in
11 cm
Minimum tank
42 gal
160 L
Temperament
Mostly peaceful
Social behavior
Schooling
Swim level
Middle
Difficulty
Medium
Breeding
No record
Rarity
Rare
Family
Danionidae
Origin
Malay Peninsula streams, Thailand and Myanmar

Overview

Bernatzik's baril is one of the warmer-water barils, so it slots into a tropical river community. It is an athletic schooler for keepers with a little experience.

Did you know

Bernatzik's baril carries the name of an Austrian anthropologist and photographer. Hugo Bernatzik was in Southeast Asia to study people, and the fish traveled home alongside his field notes.

Caring for the Bernatzik's baril

Keep Bernatzik's barils as a school of five or more. A long tank of 42 gal (160 L) or larger gives a group room to move. Add brisk current from powerheads or a strong filter return, a substrate of sand and rounded gravel, and scattered wood. They jump, so keep a tight lid, and leave open swimming length with open water above.

Keep the water well oxygenated, at 72 to 81°F (22 to 27°C) with a pH of 6.5 to 7.5. They are surface-oriented feeders. Offer floating foods along with frozen and small live items such as bloodworm, mosquito larvae and daphnia.

Bernatzik's barils are mostly peaceful. Keep them alongside large rasboras, danios and loaches that can hold their own. Their spawning is not documented in aquariums.

Good to know

Opsarius bernatziki is a danio-family baril in Danionidae. Koumans described it in 1937 and named it for Hugo Bernatzik, who collected the first specimen on one of his expeditions.

In the wild

Bernatzik's baril lives in streams of the Malay Peninsula and the Thai and Myanmar border country. The water there is clear, flowing and well-oxygenated.

Weekly picks

Tank mates

The Bernatzik's baril is a mostly peaceful, schooling species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a Bernatzik's baril need?

A Bernatzik's baril needs at least 42 gal (160 L). It spends most of its time in the middle.

What temperature and pH does a Bernatzik's baril need?

A Bernatzik's baril is comfortable at 72–81°F (22–27°C) with a pH of 6.5–7.5.

What does a Bernatzik's baril eat?

A Bernatzik's baril is a surface-oriented feeder. Offer floating foods, along with frozen and small live items such as bloodworm, mosquito larvae and daphnia.

How big does a Bernatzik's baril get?

An adult Bernatzik's baril reaches about 4.3 in (11 cm).

Does a Bernatzik's baril need a group?

Yes. A Bernatzik's baril is a schooling species and should be kept in a group, not singly.

Related species