Peacock Spiny Eel
 
Macrognathus aculeatus — Peacock Spiny Eel
Family: Mastacembelidae
Origin: Slow-moving rivers, swamps, and floodplains of Southeast Asia (Thailand, Vietnam, Indonesia, Malaysia)
Size: 15–20 cm (6–8 inches)
Lifespan: 8–15 years
 
Natural Habitat
Environment: Silty or muddy-bottomed slow-moving rivers and streams, often heavily vegetated
Water Conditions: Warm, soft to moderately hard water with dense plant cover and leaf litter
Temperature Range: 24–28°C (75–82°F)
 
Physical Description
Body Shape: Long, eel-like body with a pointed snout and small fins
Coloration: Tan to light brown with a series of black and gold eyespots (ocelli) on the dorsal fin
Fins: Small pectoral fins, elongated dorsal and anal fins; caudal fin rounded
 
Aquarium Care
Tank Size: Minimum 30 gallons; larger tanks recommended for multiple individuals
Water Parameters:
pH: 6.5–7.5
Temperature: 24–28°C (75–82°F)
Water Flow: Low to moderate
Substrate: Fine sand or smooth gravel (they like to burrow)
Décor: Driftwood, caves, soft plants, leaf litter; tight-fitting lid is essential (notorious escape artists)
Filtration: Moderate, with minimal surface agitation
 
Diet
Type: Carnivorous
Preferred Foods: Live or frozen bloodworms, blackworms, tubifex, brine shrimp; may accept sinking carnivore pellets over time
Feeding Frequency: Once daily
 
Behavior & Tank Mates
Temperament:
Generally peaceful but shy
May be territorial with other Spiny Eels or bottom dwellers
Compatible Tank Mates:
Peaceful mid- to top-dwelling species (Tetras, Gouramis, Rasboras)
Avoid aggressive fish or fin-nippers
Behavior Notes:
Nocturnal and reclusive; prefers dim lighting and hiding spaces
Can recognize owners and show interactive behavior
 
Breeding
Spawning Method: Egg scatterer
Breeding Conditions:
Very rarely bred in captivity; commercial breeding involves hormone use
Fry Care:
Fry are delicate and require live microfoods