Fish
Purple Emperor Tetra
Inpaichthys kerri
Origin: The purple emperor tetra is endemic to the Aripuanã River basin (a Madeira tributary) in Brazil. It inhabits soft, acidic forest streams and tributaries with slow flow and shade.
Also known as: Blue emperor tetra, Kerri tetra, Inpaichthys kerri
Fact sheet
- Size
- 4 cm
- Lifespan
- 4 years
- Minimum tank size
- 75 L
- Temperature
- 24–27 °C
- pH
- 5.5–7
- Hardness GH
- 2–12 °dH
- Temperament
- Peaceful
- Social behavior
- Schooling
- Group size
- 8+ individuals
- Swimming zone
- Middle
- Diet
- Omnivore
- Jumps out
- No
- Eats plants
- No
Overview
The purple emperor tetra (kerri tetra) is a graceful characin with a delicate blue-purple sheen to its body and a dark longitudinal stripe. It resembles the emperor tetra but is smaller and differs in having an adipose fin, which Nematobrycon lacks. In males the purple sheen and a reddish dot on the adipose fin are brighter. It is a peaceful schooling fish for a planted soft-water tank. It shows its purple shimmer best against a dark background in a tight shoal.
Appearance
The body is slender and elongated, 4–4.5 cm long. Colour is silvery-bluish with a delicate blue-purple sheen and a dark longitudinal stripe from head to tail. In males the purple shimmer is richer and the adipose fin has a reddish dot; females are paler with a yellowish tint. The eyes are bluish.
Care
A tank of at least 75 L, planted, with dark substrate and soft water. Temperature 24–27 °C, pH 5.5–7.0, hardness GH 2–12. Clean soft water, gentle flow, and regular water changes are needed. Diffuse light and a dark background enhance the purple sheen.
Feeding
An omnivore with a small mouth. It takes small flakes and micro-pellets and live or frozen daphnia, cyclops, brine shrimp nauplii, and micro-worm. Feed once or twice daily in small portions.
Compatibility
A peaceful schooling fish. Excellent with small peaceful characins, rasboras, corydoras, dwarf cichlids, and shrimp. Large or aggressive tankmates are unsuitable. Keep in shoals of at least 8.
Breeding
An egg-layer. Trigger spawning with soft, acidic water. The fish scatter eggs among fine-leaved plants; remove the adults. Fry hatch in a day or two; first foods are infusoria and brine shrimp nauplii.
Fun facts
The purple kerri is told from the similar emperor tetra (Nematobrycon palmeri) by the presence of an adipose fin. The purple sheen is best seen under side lighting. The species is named after the collector John Kerr.