Fish
Emperor Tetra
Nematobrycon palmeri
Origin: The emperor tetra is endemic to the San Juan and Atrato rivers of western Colombia. It inhabits slow tributaries and streams with soft, slightly acidic water, shade, and vegetation.
Also known as: Royal tetra, Nematobrycon palmeri
Fact sheet
- Size
- 6 cm
- Lifespan
- 5 years
- Minimum tank size
- 75 L
- Temperature
- 23–27 °C
- pH
- 5.5–7.5
- Hardness GH
- 2–15 °dH
- Temperament
- Peaceful
- Social behavior
- Schooling
- Group size
- 6+ individuals
- Swimming zone
- Middle
- Diet
- Omnivore
- Jumps out
- Yes
- Eats plants
- No
Overview
The emperor (royal) tetra is an elegant characin with a smoky-violet body, a longitudinal black stripe, and expressive blue-green eyes. Males are larger and showier, with elongated central tail rays forming a 'trident'. It is a hardy, relatively peaceful schooling fish well suited to beginners and to a planted community tank. In a shoal the males perform harmless displays to sort out territories. It shows best against a dark background in soft water.
Appearance
The body is slender, 5–6 cm long. Colour is smoky grey-violet with a black longitudinal stripe from head to tail and a yellow-gold zone above it; the eyes are blue-green or turquoise. In males the central tail rays are elongated into a characteristic trident and the dorsal fin is taller. Females are plainer, with golden eyes.
Care
A tank of at least 75 L with dark substrate, plants, driftwood, and open space. Temperature 23–27 °C, pH 5.5–7.5, hardness GH 2–15. Soft, slightly acidic water, good filtration with gentle flow, and regular water changes are needed. Diffuse light brings out the colour.
Feeding
An omnivore. It takes quality small flakes and pellets and live or frozen daphnia, cyclops, brine shrimp nauplii, and small bloodworm. Feed once or twice daily in small portions.
Compatibility
A relatively peaceful schooling fish. Excellent with other small tetras, rasboras, dwarf cichlids, and corydoras. It may occasionally nip very small or long-finned tankmates. Keep in shoals of at least 6–8, preferably with several males.
Breeding
Breeding is easy. Trigger spawning with soft, acidic water. The fish scatter eggs among fine-leaved plants; remove the adults as they eat the eggs. Fry hatch in a day or two; first foods are infusoria and brine shrimp nauplii.
Fun facts
The emperor tetra is easily told from the similar blue emperor tetra (Inpaichthys kerri) by its lack of an adipose fin. The elongated central-rayed 'trident' tail is the males' hallmark. Almost all fish in trade are captive-bred and very undemanding.