The Black Buenos Aires Tetra is a dark selectively bred variety of the Buenos Aires Tetra, known for its smoky black coloration, energetic schooling behavior, and hardy nature. It is a striking community fish that combines the activity of classic Buenos Aires Tetras with a more dramatic appearance.

Overview

• Scientific name: Hyphessobrycon anisitsi (black strain)

• Family: Characidae

• Origin species: South America

• Adult size: 6–8 cm (2.5–3 inches)

• Lifespan: Around 5–7 years

Black Buenos Tetras are popular because they are:

• hardy

• active

• eye-catching

• suitable for larger community aquariums

Appearance

Main characteristics:

• smoky black to charcoal-gray body

• streamlined elongated shape

• reflective metallic sheen

• active swimming posture

Some specimens may also show:

• reddish fin highlights

• silver undertones

• darker dorsal region

• translucent black fins

High-quality specimens usually display:

• even dark coloration

• healthy finnage

• active schooling behavior

• strong body shape

Their dark tones appear especially striking against green plants and lighter substrate.

Origin and genetics

Black Buenos Tetras are selectively bred from:

• Buenos Aires Tetra bloodlines

• darker pigmentation strains

Breeders focused on enhancing:

• black coloration

• metallic sheen

• hardiness

• schooling behavior

This strain retains most behavioral traits of the standard Buenos Aires Tetra.

Temperament

Black Buenos Tetras are:

• active

• social

• semi-peaceful

• energetic schooling fish

Recommended:

• keep at least 8–10 individuals

In small groups they may become:

• fin nippy

• territorial toward weaker fish

Larger schools reduce aggression and improve natural behavior.

They are best suited for:

• active community aquariums

Aquarium setup

Minimum tank size

• Around 100 liters (25 gallons)

Ideal setup

• spacious aquarium

• open swimming space

• moderate water flow

• sturdy plants

Popular décor:

• driftwood

• rocks

• Vallisneria

• Anubias

• Java fern

Because they are fast swimmers, open areas are important.

Water parameters

Recommended conditions:

• Temperature: 20–28°C

• pH: 6.0–7.5

• Soft to moderately hard water

• Ammonia/Nitrite: 0

• Low nitrate levels

They are relatively adaptable and hardy.

Diet

Black Buenos Tetras are omnivores.

Common foods:

• quality flakes

• pellets

• frozen bloodworms

• brine shrimp

• daphnia

• vegetable-based foods

They are enthusiastic feeders and benefit from:

• varied nutrition

• occasional plant matter

A balanced diet helps maintain:

• dark coloration

• activity

• overall health

Compatibility

Suitable tankmates:

• larger tetras

• rainbowfish

• danios

• peaceful barbs

• corydoras

• medium community fish

Avoid:

• slow long-finned fish

• delicate species

• tiny shrimp

They may nip fins if:

• overcrowded

• under-socialized

Plant compatibility

Like standard Buenos Aires Tetras:

• they may nibble soft plants

Better plant choices include:

• Java fern

• Anubias

• Vallisneria

• hardy stem plants

Delicate soft-leaf plants may be damaged.

Breeding

Breeding is moderately easy.

Breeding behavior:

1. Pair or group spawning

2. Egg scattering among plants

3. No parental care

Breeding setup:

• separate spawning tank

• soft slightly acidic water

• fine-leaf plants or spawning mops

Eggs usually hatch within:

• 24–36 hours

Fry foods:

• infusoria

• powdered fry foods

• baby brine shrimp later

Adults may eat eggs and fry.

Common health problems

Fin damage

Can occur due to:

• fin nipping

• overcrowding

Stress fading

Possible causes:

• poor water quality

• unstable conditions

Ich

Symptoms:

• white spots

• scratching behavior

They are generally hardy under proper care.

Care difficulty

Black Buenos Tetras are:

• beginner-friendly to intermediate-level fish

Main requirements:

• schooling groups

• swimming space

• stable water quality

• active compatible tankmates

They are adaptable and durable once established.

Difference from Standard Buenos Aires Tetra

Compared to Buenos Aires Tetra:

• Black Buenos Tetras display darker smoky coloration

• Standard strains usually show silver bodies with red fins

Behavior and care remain very similar.

Why aquarists value them

Black Buenos Tetras are admired for:

• dramatic dark coloration

• energetic schooling behavior

• hardy nature

• active aquarium presence

A large healthy school creates a bold and dynamic freshwater display in spacious planted aquariums.