Brown ghost knifefish
Apteronotus leptorhynchus
FreshwaterFish
Care at a glance
- Temperature
- 75–84°F
- 24–29°C
- pH
- 6.5–7.5
- Adult size
- 11.8 in
- 30 cm
- Minimum tank
- 85 gal
- 320 L
- Temperament
- Mostly peaceful
- Social behavior
- Solitary
- Tankmates
- With caution
- Swim level
- Middle
- Diet
- Carnivore
- Difficulty
- Difficult
- Breeding
- No record
- Rarity
- Very rare
- Family
- Apteronotidae
- Origin
- Colombia, Venezuela
Overview
The brown ghost knifefish is a large, night-active knifefish for a big, shaded freshwater tank. It is for experienced keepers.
Did you know
The brown ghost knifefish can tell live prey from background clutter by reading distortions in its own electric field. That lets it hunt well in pitch darkness. Researchers study it a lot because each fish holds a slightly different electric frequency, almost like a personal signature.
Caring for the brown ghost knifefish
Plan on a tank of at least 85 gal (320 L) for a single brown ghost knifefish. It is most active at night and hides during the day, so give it a heavily shaded tank with caves, driftwood and a soft substrate. It cruises the middle of the tank after dark.
This demanding fish needs clean, stable water that is slightly soft, at 75 to 84°F (24 to 29°C) and a pH of 6.5 to 7.5. Feed a steady supply of meaty foods, such as frozen bloodworms, brine shrimp and chopped earthworms.
Keep it on its own, because it is solitary and turns territorial with its own kind and other knifefish. It is mostly peaceful with calm tank mates too big to eat. It is easily bullied at feeding time, so keep mealtimes generous.
Good to know
The brown ghost knifefish, Apteronotus leptorhynchus, is a knifefish in the family Apteronotidae. It is not a true eel, despite its long, ribbon-like body. It is a big fish that lives a long time, often well over a decade in good conditions. Like its relatives, it produces a weak, continuous electric field for sensing its surroundings and communicating.
In the wild
Brown ghost knifefish come from slow rivers and streams in Colombia and Venezuela. They live in dim, tannin-stained water with roots, leaf litter and plenty of cover.
Common questions
What size tank does a brown ghost knifefish need?
A brown ghost knifefish needs at least 85 gal (320 L). It spends most of its time in the middle.
What temperature and pH does a brown ghost knifefish need?
A brown ghost knifefish is comfortable at 75–84°F (24–29°C) with a pH of 6.5–7.5.
What does a brown ghost knifefish eat?
A brown ghost knifefish eats meaty foods, such as frozen bloodworms, brine shrimp and chopped earthworms. Keep its meals generous, since tank mates can bully it at feeding time.
How big does a brown ghost knifefish get?
An adult brown ghost knifefish reaches about 11.8 in (30 cm).
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