Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Inpaichthys kerri

Blue emperor tetra

Blue emperor tetra, Inpaichthys kerriBlue emperor tetra, Inpaichthys kerri
Photos by Andy Rapson


Inpaichthys: It is a dedication name; from a Brazilian institution about Indian tribes.

General Notes:

Blue emperor tetras are peaceful and slightly timid, they should be kept in groups of at least five individuals and with other small peaceful fishes. Avoid tank mates with long flowing fish because this fish could be tempted to nip the fins of such fish. Most aggression is mild and restricted to their own kind.


Unfussy eater, use a good quality flake food and supplement with suitably sized live or frozen food to ensure a varied and balanced diet.


Males are smaller and more colourful, females have a red adipose fin while the males have a blue adipose fin. (See photos).


Not the easiest Tetra to breed, try using a standard tetra set up to breed them:

Use a separate aquarium filled with soft acidic aged water and containing a small air powered sponge filter and something to act as a spawning mop such as a bunch of fine leaved plants tied in to a bunch for example. Keep the tank away from direct light and in very dim conditions because both eggs and fry of this species are light sensitive. Introduce a well conditioned pair in the evening and they will probably spawn at dawn. After spawning remove the parents to prevent them from eating all their eggs. The eggs hatch after about 30 hours but it will be another three or four days before the fry become free swimming. Add a commercially available liquid fry food to the tank about a day or so before the fry become free swimming as this will encourage the growth of infusoria which the fry can eat but don't add to much and pollute the water. Carry on using the liquid food or similar until the fry are large enough to take micro worms or newly hatched brine shrimps. Blue emperor tetras can be bred as a pair or in a group. If you breed them in a group be aware that you will have a very large number of fry which will require a great deal of space to raise and dealers won't thank you if you flood the local market with these fish and they end up stuck with them.

Wild status

The wild status of this species has not yet been evaluated.

Information at a glance

pH: 6 - 7.5
dGH: 4 - 15
Temperature: 24 - 27°C (76 - 80°F)
Diet: Omnivore
Size: 2.8cm (1.25in)
Min tank size: 60 litres
Difficulty level: Easy
Aquarium type: Community
Swimming level: Middle

Distribution and habitat

distribution map for Blue emperor tetra, Inpaichthys kerri

Origin: South America: Aripuanã River, upper Madeira River basin, Mato Grosso, Brazil.

Habitat: Forest streams


Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Characiformes
Family: Characidae
Genus: Inpaichthys
Species: I. kerri Géry & Junk, 1977

Common name:
Blue emperor tetra

Synonyms: None