Elephant nose fish

Quick facts

Adult size

22 cm

Lifespan

can live up to 10 years

Tank zone

bottom

Temperament

peaceful

Difficulty

advanced

Typically wild-caught

yes - acclimate slowly

Water parameters

Temperature

24–28°C

pH

6.0 to 7.5

Hardness

2 to 12 dGH

Tank requirements

Minimum volume

200 L

Minimum length

100 cm

Flow

low

Lighting

dim preferred

Substrate

sand

Driftwood

preferred

Hiding spots

needed

Open swimming room

needed

Feeding

Diet: carnivore, feeds primarily at the bottom.

Frozen bloodworms (the dietary staple for most elephant noses), live blackworms, frozen brine shrimp. Refuses dry food almost universally. Feeds by probing the substrate with the trunk-like chin extension. Shy feeder; aggressive tankmates steal food before the elephant nose finds it.

Nocturnal feeder; drop food after lights out so it can eat without competition.

Compatibility

• Generates a weak electric field from a modified muscle near the tail and uses it to navigate, find food, and communicate with conspecifics. The 'trunk' (actually the lower jaw) is covered in electroreceptors
• Intelligent by fish standards. Has the largest brain-to-body-weight ratio of any fish. Learns to recognize its keeper and feeding schedule
• Sensitive to water quality and medication. Scaleless fish protocols apply: half-dose copper treatments, no salt. Dies quickly in deteriorating water
• Keep one or keep five+. Two or three fight; a single fish is fine; a group of five or more distributes aggression. The middle ground is the problem
• Nocturnal. Dim lighting and plenty of hiding spots required. Rarely visible during the day in brightly lit tanks

Habitat

Native to muddy, slow-moving rivers in West and Central Africa. Produces weak electric fields from a specialized organ in the caudal peduncle and detects objects, prey, and other electric fish using receptors in the elongated chin. This electrolocation system works like sonar in murky water where vision is useless. The "trunk" (Schnauzenorgan) probes into crevices and soft substrate to find insect larvae. One of the more unusual freshwater fish available, but demanding to keep properly.

Breeding

Not bred in home aquariums. They use weak electric fields for navigation and communication, and the electrical environment in a home tank doesn't support the complex courtship behaviors observed in the wild. All specimens in the trade are wild-caught from West African rivers.

Common problems

Extremely sensitive to water quality and medications. Scaleless and therefore intolerant of many common treatments. The elongated snout (actually a chin extension, called a Schnauzenorgan) is a sensory organ used to find food in the substrate; it is fragile and can be damaged by rough substrates or aggressive tankmates. They're nocturnal, shy, and often starve in community tanks because they're too slow to compete for food. Target-feed with frozen bloodworm after lights-out. Only one per tank unless the tank is very large (300 L) and heavily structured; they're aggressive toward conspecifics.

Bioload

Bioload coefficient: 5.0 (medium-large oddball; moderate-heavy waste from high-protein diet).

Bioload coefficients are calibrated against the neon tetra as the anchor (1.0). See the methodology page for the formula and how each value was derived.

Further reading

• How to cycle a fish tank
• Stocking ideas by tank size