The Red Phantom Tetra is a peaceful South American schooling fish admired for its translucent red coloration, elegant body shape, and calm community behavior. It is one of the most attractive soft-water tetras for planted aquariums.

Overview

• Scientific name: Hyphessobrycon sweglesi

• Family: Characidae

• Origin: Colombia and the Orinoco basin

• Adult size: 4–5 cm (1.5–2 inches)

• Lifespan: Around 4–6 years

Red Phantom Tetras are popular because of their:

• glowing red-orange coloration

• peaceful temperament

• schooling behavior

• suitability for planted aquariums

Appearance

Main characteristics:

• translucent red to orange-red body

• laterally compressed shape

• black shoulder patch behind the gills

• flowing dorsal and anal fins

Males usually display:

• deeper red coloration

• longer darker fins

• stronger contrast

Females are typically:

• slightly paler

• rounder-bodied

• smaller-finned

High-quality specimens usually show:

• vivid red coloration

• clear shoulder patch

• healthy finnage

• active schooling behavior

Their colors become especially intense under subdued lighting and dark substrate.

Natural habitat

In the wild, Red Phantom Tetras inhabit:

• slow-moving forest streams

• blackwater tributaries

• flooded vegetation zones

• soft acidic waters

Natural habitat features include:

• leaf litter

• submerged roots

• dim lighting

• tannin-rich water

Temperament

Red Phantom Tetras are:

• peaceful

• social

• active

• schooling fish

Recommended:

• keep at least 8–10 individuals

Males may engage in:

• harmless display sparring

• fin spreading

• territorial posturing

These behaviors rarely cause injury.

They are excellent for peaceful community aquariums.

Aquarium setup

Minimum tank size

• Around 75 liters (20 gallons)

Ideal setup

• planted aquarium

• driftwood

• dark substrate

• subdued lighting

• open swimming areas

They thrive in:

• blackwater aquariums

• planted nature tanks

• soft-water community setups

Floating plants help reduce stress and intensify coloration.

Water parameters

Recommended conditions:

• Temperature: 23–28°C

• pH: 5.5–7.0

• Soft to moderately soft water

• Ammonia/Nitrite: 0

• Low nitrate levels

Stable clean water is important for:

• vivid coloration

• fin health

• breeding condition

Diet

Red Phantom Tetras are omnivores.

Common foods:

• quality flakes

• micro pellets

• frozen bloodworms

• daphnia

• baby brine shrimp

• small live foods

A varied diet helps maintain:

• coloration

• activity

• immune health

They mainly feed in the mid-water region.

Compatibility

Suitable tankmates:

• rasboras

• peaceful tetras

• corydoras

• pencilfish

• dwarf cichlids

• peaceful gouramis

Avoid:

• aggressive fish

• fin nippers

• large predators

They perform best in calm community tanks.

Breeding

Breeding is possible in soft acidic water.

Breeding behavior:

1. Pair formation

2. Courtship displays

3. Egg scattering among plants

4. No parental care

Breeding setup:

• dim lighting

• fine-leaf plants or spawning mops

• soft acidic water

Eggs usually hatch within:

• 24–36 hours

Fry foods:

• infusoria

• powdered fry foods

• baby brine shrimp later

Adults may consume eggs and fry.

Common health problems

Color fading

Often caused by:

• stress

• bright lighting

• poor water quality

Ich

Symptoms:

• white spots

• scratching behavior

Fin damage

Possible causes:

• rough tankmates

• poor maintenance

Good water quality greatly improves health and coloration.

Care difficulty

Red Phantom Tetras are:

• beginner to intermediate-level fish

Main requirements:

• schooling groups

• peaceful environment

• stable water conditions

• planted setup

They adapt well once established.

Difference from Black Phantom Tetra

Compared to Black Phantom Tetra:

• Red Phantom Tetras display translucent red-orange coloration

• Black Phantom Tetras show smoky gray-black tones

Both share similar body shape and behavior.

Why aquarists value them

Red Phantom Tetras are admired for:

• glowing red coloration

• elegant fin displays

• peaceful schooling behavior

• compatibility with planted aquariums

A healthy school moving through a dimly lit planted aquarium creates a warm and highly natural freshwater display.