
Boulenger’s Featherfin Tetra
Bryconaethiops boulengeri
- Care level
- Advanced
- Adult size
- 25 cm
- Minimum tank
- 243 litres
- Temperature
- 22–26 °C
Species profile
Inpaichthys kerri
Common names: Blue Purple Emperor Tetra, Blue Emperor Tetra, Royal Tetra

A pretty little tetra, also sold as the Blue Emperor, Regal or Royal Tetra. Keep a group of at least 6 in 87 litres or more.
A pretty little tetra, also sold as the Blue Emperor, Regal or Royal Tetra. Males are metallic blue with a dark stripe, and females are stockier and plainer.
Check the scientific name when buying, as common names vary between sellers and countries.
Mature females are usually rounder in the belly, and males are usually slimmer and often brighter.
A long tank with open swimming water, plants around the edges and steady filtration suits this fish. A darker substrate and some floating plants usually bring out its colour.
Active and social, and most settled when kept with its own kind.
Keep a group of at least 6, and more if you can. Larger groups are calmer and show better colour and behaviour.
Not territorial, although males may spar and display.
Suits a community of similar-sized, peaceful fish that like the same water. Avoid large predators, which will treat it as food. It may nip the fins of slow or long-finned fish, and a larger group usually reduces this. It may eat baby shrimp.
Fairly tolerant of different water, if it is clean and stable. Keep the temperature steady.
Feeds on small invertebrates in the wild. Offer quality flake and micro pellets with frozen daphnia and brine shrimp.
Feed small amounts, and remove anything left after a few minutes.
An egg scatterer with no parental care. Adults eat eggs and fry, so use a separate tank with fine plants, moss or mesh on the bottom, and remove the adults after spawning. The fry need very small foods at first.
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