Emperor tetra
Nematobrycon palmeri
FreshwaterFish
Care at a glance
- Temperature
- 73–81°F
- 23–27°C
- pH
- 5.5–7.5
- Adult size
- 2 in
- 5 cm
- Minimum tank
- 20 gal
- 75 L
- Temperament
- Mostly peaceful
- Social behavior
- Schooling
- Swim level
- Middle
- Difficulty
- Easy
- Breeding
- Egg scatterer · Medium
- Rarity
- Common
- Family
- Characidae
- Origin
- Colombia
Overview
The emperor tetra is a mostly peaceful schooling fish for a planted community tank. It is easy to keep, even in a first tank.
Did you know
Adult emperor tetras have blue-green eyes that catch the light, which is unusual for a tetra.
Caring for the emperor tetra
Keep emperor tetras in a group of six or more, in a tank of at least 20 gal (75 L). Plant it, keep the lighting subdued and leave some open swimming room.
Hold the water at 73 to 81°F (23 to 27°C) with a pH of 5.5 to 7.5. They sit comfortably in soft to moderately hard water. A varied diet of quality flake, micro pellets and frozen brine shrimp or daphnia keeps them in good shape.
Emperor tetras are mostly peaceful, but males can squabble over territory, so keep a few females per male. A dominant male holds his fins flared and patrols a small patch of the tank. He displays to females and warns off rival males.
Males have the middle rays of the tail fin extended. The fish scatter their eggs and give no parental care, and the eggs hatch in roughly a day. Breeding them takes moderate effort.
Good to know
The emperor tetra is a member of the family Characidae, with an elongated body and a forked tail. The species is listed as Least Concern, with stable wild populations.
In the wild
Emperor tetras live in slow streams and rivers of the San Juan and Atrato basins in Colombia, usually in the shade of overhanging plants. The water runs slightly acidic to neutral over sand or fine gravel.
Weekly picks
Tank mates
The emperor tetra 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.
Neocaridina shrimp
Neocaridina davidi
Freshwater1.6 in (4 cm) · 5 gal (19 L)59–84°F (15–29°C)
Guppy
Poecilia reticulata
FreshwaterBrackish2.4 in (6 cm) · 10 gal (38 L)64–82°F (18–28°C)
Neon tetra
Paracheirodon innesi
Freshwater1.5 in (3.8 cm) · 11 gal (40 L)70–77°F (21–25°C)
Barito loach
Kapuasia falaris
Freshwater2.6 in (6.5 cm) · 20 gal (75 L)73–81°F (23–27°C)
Kuekenthal's halfbeak
Hemirhamphodon kuekenthali
Freshwater3.3 in (8.5 cm) · 20 gal (75 L)73–81°F (23–27°C)
Marble wood shrimp
Atya scabra
Freshwater3.9 in (10 cm) · 20 gal (75 L)73–82°F (23–28°C)
Common questions
What size tank does an emperor tetra need?
An emperor tetra needs at least 20 gal (75 L). It spends most of its time in the middle.
What temperature and pH does an emperor tetra need?
An emperor tetra is comfortable at 73–81°F (23–27°C) with a pH of 5.5–7.5.
What does an emperor tetra eat?
An emperor tetra eats quality flake, micro pellets and frozen brine shrimp or daphnia. A varied mix of these keeps it in good shape.
How big does an emperor tetra get?
An adult emperor tetra reaches about 2 in (5 cm).
Does an emperor tetra need a group?
Yes. An emperor tetra is a schooling species and should be kept in a group, not singly.
How can you tell a male emperor tetra from a female?
Males have the middle rays of the tail fin extended.
How does an emperor tetra breed?
Emperor tetras are egg scatterers that give no parental care. The eggs hatch in roughly a day, and breeding takes moderate effort.
Related species
2 in (5 cm)20 gal (75 L)73–81°F (23–27°C)Rainbow emperor tetra
Nematobrycon lacortei
2 in (5 cm) · 20 gal (75 L)
2 in (5 cm)22 gal (85 L)72–79°F (22–26°C)Blue tetra
Knodus borki
2 in (5 cm) · 22 gal (85 L)
2 in (5 cm)18 gal (70 L)75–82°F (24–28°C)Glass tetra
Moenkhausia oligolepis
2 in (5 cm) · 18 gal (70 L)
2 in (5 cm)20 gal (75 L)72–79°F (22–26°C)Green fire tetra
Aphyocharax rathbuni
2 in (5 cm) · 20 gal (75 L)
2.2 in (5.5 cm)20 gal (75 L)72–82°F (22–28°C)Bloodfin tetra
Aphyocharax anisitsi
2.2 in (5.5 cm) · 20 gal (75 L)
1.8 in (4.5 cm)17 gal (65 L)68–82°F (20–28°C)Serpae tetra
Hyphessobrycon eques
1.8 in (4.5 cm) · 17 gal (65 L)