Brown Ghost Knife (Apteronotus leptorhynchus)

Brown ghost knives are something of a celebrity in neuroscience circles — Apteronotus leptorhynchus is one of the most heavily studied electric fish in research on how nervous systems process sensory information, prized for a stable, easy-to-record electric organ discharge. In the home aquarium, that same electric sense just means a shy, nocturnal fish that navigates and hunts perfectly well in total darkness.

Care level: Moderate · Temperament: Peaceful, territorial with own kind · Max size: ~19" · Min tank: 100+ gal (adult) · Diet: Carnivore, live/frozen foods