Royal tetra
Inpaichthys kerri
Also known as Blue Emperor Tetra
FreshwaterFish
Care at a glance
- Temperature
- 75–81°F
- 24–27°C
- pH
- 5.5–7.5
- Adult size
- 1.4 in
- 3.5 cm
- Minimum tank
- 15 gal
- 55 L
- Temperament
- Peaceful
- Social behavior
- Schooling
- Swim level
- Middle
- Difficulty
- Beginner
- Breeding
- Medium
- Rarity
- Common
- Family
- Characidae
- Origin
- Brazil
Overview
Keep them in a group of six or more in a tank of around 55 liters, where they stay active in the middle levels. They are peaceful and do well in a calm community with other small, gentle fish. Feed quality flake or micro-pellets plus occasional live or frozen foods such as brine shrimp, daphnia, and bloodworms. They want soft, slightly acidic to neutral water, pH about 5.5 to 7.5, and temperatures in the mid 20s C.
In the wild
Royal tetras are found in the Brazilian Amazon, including the Rio Aripuana drainage. They favor slow or still water over soft, sandy or muddy bottoms, shaded by dense forest canopy that keeps the light low and the water soft and slightly acidic. A planted tank with subdued lighting, fine substrate, and some driftwood gives them what they are used to. Tannin-stained water is a bonus, not a requirement.
Good to know
This characin in the family Characidae is small, reaching about 3.5 cm. The body carries an iridescent blue to violet sheen with a dark lateral stripe, and males tend to show stronger color. They are egg scatterers that spawn among plants and give no parental care. They are not listed as threatened, though Amazon habitat loss is a background concern.
Did you know
Royal tetras are often confused with the emperor tetra at a glance, but they have an adipose fin (the small fin between the dorsal and tail) that the emperor tetra lacks. That little fin is a quick way to tell the two apart in a mixed shop tank.
Weekly picks
Tank mates
Royal tetra is a 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.
Amazon sail-fin dwarf cichlid
Apistogramma pertensis
Freshwater2 in (5 cm) · 15 gal (55 L)77–84°F (25–29°C)
Clown killifish
Epiplatys annulatus
Freshwater1.4 in (3.5 cm) · 15 gal (55 L)68–79°F (20–26°C)
Barred pencilfish
Nannostomus espei
Freshwater1.2 in (3 cm) · 15 gal (55 L)72–82°F (22–28°C)
Apiaka cory
Hoplisoma apiaka
Freshwater1.8 in (4.5 cm) · 15 gal (55 L)75–82°F (24–28°C)
Fire halfbeak
Hemirhamphodon kapuasensis
Freshwater2.4 in (6 cm) · 14 gal (54 L)73–81°F (23–27°C)
Southern platy
Xiphophorus maculatus
Freshwater2.8 in (7 cm) · 15 gal (55 L)68–79°F (20–26°C)
Common questions
What size tank does a Royal tetra need?
A Royal tetra needs at least 15 gal (55 L). It spends most of its time in the middle.
What temperature and pH does a Royal tetra need?
A Royal tetra is comfortable at 75–81°F (24–27°C) with a pH of 5.5–7.5.
How big does a Royal tetra get?
An adult Royal tetra reaches about 1.4 in (3.5 cm).
Does a Royal tetra need a group?
Yes. A Royal tetra is a schooling species and should be kept in a group, not singly.
Related species
1.4 in (3.5 cm)14 gal (54 L)72–81°F (22–27°C)Black arrow tetra
Inpaichthys luizae
1.4 in (3.5 cm) · 14 gal (54 L)
1.3 in (3.4 cm)14 gal (54 L)73–81°F (23–27°C)Nambiquara royal tetra
Inpaichthys nambiquara
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