Description
Black Ghost Knife Fish (Apteronotus albifrons)
📌 Basic Info
Scientific Name: Apteronotus albifrons
Common Names: Black Ghost Knife, BGK
Family: Apteronotidae
Order: Gymnotiformes
Origin: Amazon Basin, Paraguay, and Paraná Rivers (South America)
Size: Up to 18 – 20 inches (45 – 50 cm)
Lifespan: 10 – 15 years
Tank Zone: Bottom to mid dweller
🌊 Water Parameters
TDS: 100 – 250 ppm
pH: 6.5 – 7.5
Temperature: 25 – 28°C (77 – 82°F)
Hardness: 2 – 10 dGH
🐟 Characteristics
Body: Jet black, elongated body with a smooth, ribbon-like movement; white markings on the tail and sometimes on the head.
Behavior: Peaceful and intelligent but can be territorial with other knifefish.
Movement: Uses a continuous undulating fin to move gracefully both forward and backward.
Unique Feature: Generates weak electric pulses for navigation and communication (electroreception).
Nature: Nocturnal and prefers dimly lit or dark environments.
🍽️ Food
Type: Carnivorous
Diet: Bloodworms, tubifex, chopped shrimp, brine shrimp, blackworms, and high-protein sinking pellets.
Feeding: Feed at night or when lights are dimmed; small portions twice daily.
🛠️ Maintenance
Tank Size: Minimum 100 gallons (380 L) for an adult.
Filtration: Strong filtration; needs clean, oxygen-rich water.
Decor: Provide caves, driftwood, smooth rocks, and hiding tunnels.
Lighting: Low to moderate lighting; prefers shaded zones.
Water Change: 25 – 30% weekly.
👥 Social Behavior
Minimum Group Size: Best kept singly (territorial with other knifefish).
Tank Mates: Peaceful species like Silver Dollars, Angelfish, Gouramis, Corydoras, or larger Tetras.
Avoid: Aggressive fish (Cichlids, Arowanas) and fin-nippers (Tiger Barbs).
✅ Do’s
Provide hiding spaces and dim lighting.
Keep water conditions stable and clean.
Feed a varied protein-based diet.
Use soft substrate to avoid injury.
❌ Don’ts
Don’t keep with other knife fish species.
Don’t expose to bright lights or sudden water changes.
Don’t keep in small tanks or poor water quality.
⭐ Quick Tips
The Black Ghost Knife Fish is a graceful, electric-sensing species admired for its intelligence and unique swimming style.
Perfect for experienced aquarists who can provide a large, calm, and well-maintained aquarium.





