Banded knifefish
Gymnotus carapo
Also known as Carapo knifefish, Tuvira
FreshwaterFish
Care at a glance
- Temperature
- 73–82°F
- 23–28°C
- pH
- 6.0–7.5
- Adult size
- 15.7 in
- 40 cm
- Minimum tank
- 79 gal
- 300 L
- Temperament
- Aggressive
- Social behavior
- Solitary
- Own kind
- One per tank
- Tankmates
- With caution
- Swim level
- Bottom
- Difficulty
- Medium
- Breeding
- Hard
- Rarity
- Rare
- Family
- Gymnotidae
- Origin
- Native to slow rivers, floodplains and swamps across much of South America, hiding among submerged roots and leaf litter.
Overview
Reaching around 40 cm, it needs at least 300 litres with plenty of caves, wood and dim lighting. Keep it at 23 to 28 C and pH 6.0 to 7.5. It is predatory and territorial, so keep it singly and only with tankmates too large to eat. Feed earthworms, prawns, bloodworm and other meaty foods after dark.
In the wild
The banded knifefish is a South American electric fish with a tapering, knife-like body banded in brown and cream. It swims by rippling a long fin under the body, moving smoothly forward or backward. It is nocturnal and finds its way by generating a weak electric field.
Good to know
Gymnotus carapo produces a weak electric discharge used for navigation and communication in dark, murky water. It commonly reaches around 40 cm, with wild fish occasionally larger. It is an air-gulping predator active mainly at night.
Did you know
The banded knifefish reads its surroundings with a self-generated electric field, so it can hunt and steer in complete darkness.
Common questions
What size tank does a Banded knifefish need?
A Banded knifefish needs at least 79 gal (300 L). It spends most of its time in the bottom.
What temperature and pH does a Banded knifefish need?
A Banded knifefish is comfortable at 73–82°F (23–28°C) with a pH of 6.0–7.5.
How big does a Banded knifefish get?
An adult Banded knifefish reaches about 15.7 in (40 cm).
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