Shortfin baby whale

Care at a glance

Overview

A hardy but sensitive elephantfish for a quiet, dimly lit tank. Keep it singly, as it does not reliably tolerate its own kind in the space a home aquarium provides, and pick tankmates with caution: calm, similarly sized fish that will not outcompete it. Provide soft sand, plenty of wood and rock cover, low light, and very stable water, and never treat the tank with copper. Feed meaty foods such as bloodworm and blackworm, leaning on live and frozen items, after dark. A tank of around 200 liters suits this 20 cm fish.

In the wild

Brienomyrus brachyistius lives in the coastal rivers and streams of West Africa, hunting through leaf litter and cover in warm, soft, slow water. Recreate that with a soft substrate, botanicals and driftwood, dim lighting, and gentle filtration. Keep the water warm at 24-28 C and soft to neutral, around pH 6-7.5, and hold conditions very steady. As a wild-caught, electrically sensitive fish it needs clean water and calm surroundings to thrive.

Good to know

This elephantfish of the family Mormyridae reaches about 20 cm and communicates through a weak electric organ discharge from its tail. It is a favourite research subject, because the shape of its discharge encodes species, sex, and social rank, and each fish has its own individually distinct signal. It belongs to the small West African baby whales. Its breeding is not established in aquaria.

Did you know

Every individual produces an electric pulse of slightly different shape, so researchers can tell one fish from another by its discharge alone, in much the same way a voiceprint identifies a person.

Common questions

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