TankBud

Argentine pearlfish

Austrolebias bellottii

Also known as Argentine pearl killifish, Bellotti's pearlfish, Cynolebias bellottii

FreshwaterFish

Argentine pearlfish (Austrolebias bellottii)

Care at a glance

Temperature
61–75°F
16–24°C
pH
6.5–7.5
Adult size
2.8 in
7 cm
Minimum tank
14 gal
54 L
Temperament
Aggressive
Social behavior
Solitary
Tankmates
With caution
Swim level
Bottom
Diet
Carnivore
Difficulty
Medium
Breeding
Egg burier · Medium
Rarity
Rare
Family
Rivulidae
Origin
Native to seasonal pools and marshes of the Rio de la Plata basin in Argentina and Uruguay.

Overview

The Argentine pearlfish is a large, predatory annual killifish for a cool species tank. It is a step up from the easiest fish.

Did you know

The Argentine pearlfish's eggs wait out the dry season buried in the mud, through diapause.

Caring for the Argentine pearlfish

Give a pair or trio of Argentine pearlfish a species tank of 14 gal (54 L) or more. Use a dark, soft substrate with a deep peat layer, and keep the tank well covered.

The Argentine pearlfish does best cooler than tropical species, at 61 to 75°F (16 to 24°C) and a pH of 6.5 to 7.5. It can take a winter dip toward the cool end of that range.

Feed meaty live and frozen foods such as blackworm, bloodworm, chopped earthworm and brine shrimp. Males are aggressive toward each other and will eat small tank mates, so keep the species on its own.

Males are deep bodied and dark blue-gray, with rows of light pearly spots. They are much larger and bolder than the plain females. The pair dives straight down into the peat to spawn, pressing the eggs into the soft bottom. Breeding them takes some experience.

Good to know

Austrolebias bellottii is an annual killifish from a temperate climate, in the family Rivulidae. It was long known under the older genus name Cynolebias. It is also called Bellotti's pearlfish.

In the wild

The Argentine pearlfish is native to the Rio de la Plata basin in Argentina and Uruguay. It lives in temporary pools, marshes and flooded grassland on the temperate South American pampas. These pools dry up in summer.

Common questions

What size tank does an Argentine pearlfish need?

An Argentine pearlfish needs at least 14 gal (54 L). It spends most of its time in the bottom.

What temperature and pH does an Argentine pearlfish need?

An Argentine pearlfish is comfortable at 61–75°F (16–24°C) with a pH of 6.5–7.5.

What does an Argentine pearlfish eat?

An Argentine pearlfish eats meaty live and frozen foods, such as blackworm, bloodworm, chopped earthworm and brine shrimp.

How big does an Argentine pearlfish get?

An adult Argentine pearlfish reaches about 2.8 in (7 cm).

How can you tell a male Argentine pearlfish from a female?

Males are deep bodied and dark blue-gray, with rows of light pearly spots. They are much larger and bolder than the plain females.

How does an Argentine pearlfish breed?

Argentine pearlfish spawn in a deep layer of peat. The pair dives straight down into it, pressing the eggs into the soft bottom. Breeding them takes some experience.

Related species