Black ghost knifefish
Apteronotus albifrons
FreshwaterFish
Care at a glance
- Temperature
- 75–82°F
- 24–28°C
- pH
- 6.0–8.0
- Adult size
- 17.7 in
- 45 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
- Rare
- Family
- Apteronotidae
- Origin
- South America
Overview
The black ghost knifefish is a large, night-active freshwater fish from South America. It is mostly peaceful, but it is a fish for experienced keepers.
Did you know
The black ghost knifefish senses the world through electricity. An organ near its tail generates a weak electric field, and the fish reads its distortions to find prey and navigate in total darkness. Its eyesight is poor, so it barely relies on sight.
Caring for the black ghost knifefish
Keep a black ghost knifefish in at least 85 gal (320 L), and plan on more as it matures. Give it a dimly lit tank with plenty of shaded hiding places, plus a long tube or cave it can back into for security. It is active at night and hides by day.
Its delicate, scaleless skin needs soft sand and pristine, stable water. Keep the flow steady and the water well filtered, at 75 to 82°F (24 to 28°C) and a pH of 6.0 to 8.0. Feed live and frozen foods such as bloodworms, blackworms and shrimp in the evening.
Keep it singly, because adults are territorial toward their own kind. Choose calm, medium to large tank mates, since it could eat small fish after dark. Captive breeding is rarely documented.
Good to know
The black ghost knifefish, Apteronotus albifrons, belongs to the family Apteronotidae and is one of the largest aquarium knifefish. It swims by undulating a long anal fin, which lets it glide forward and backward with equal ease.
In the wild
The black ghost knifefish ranges widely through South American rivers, from Venezuela to the Paraguay and Parana system and the Amazon basin. It lives in warm, softly flowing water near sunken wood and root tangles.
Common questions
What size tank does a black ghost knifefish need?
A black ghost knifefish needs at least 85 gal (320 L). It spends most of its time in the middle.
What temperature and pH does a black ghost knifefish need?
A black ghost knifefish is comfortable at 75–82°F (24–28°C) with a pH of 6.0–8.0.
What does a black ghost knifefish eat?
A black ghost knifefish eats live and frozen foods such as bloodworms, blackworms and shrimp, fed in the evening. It could also eat small tank mates after dark.
How big does a black ghost knifefish get?
An adult black ghost knifefish reaches about 17.7 in (45 cm).
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