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Blackedge spiny eel

Mastacembelus nigromarginatus

Also known as Nigromarginatus eel

FreshwaterFish

Blackedge spiny eel (Mastacembelus nigromarginatus)

Care at a glance

Temperature
73–82°F
23–28°C
pH
6.0–7.5
Adult size
19.7 in
50 cm
Minimum tank
106 gal
400 L
Temperament
Mostly peaceful
Social behavior
Solitary
Tankmates
With caution
Swim level
Bottom
Diet
Carnivore
Difficulty
Medium
Breeding
No record
Rarity
Rare
Family
Mastacembelidae
Origin
Niger and Volta basins

Overview

The blackedge spiny eel is a large, solitary African eel for a long, spacious tank. It suits a keeper with a little experience.

Did you know

The blackedge spiny eel's species name, nigromarginatus, simply means black-margined. A thin dark line runs along the outer edge of its dorsal and anal fins for almost the whole length of the fish. That trim is the quickest way to tell it from other African eels.

Caring for the blackedge spiny eel

Give the blackedge spiny eel a long tank of at least 106 gal (400 L). Weight the cover firmly, because a fish this size finds any loose lid. Lay a deep, soft sand floor for it to burrow in, with driftwood, shady retreats and several pipes or rock caves to claim. A secure hide by day is what keeps it settled.

Keep the water soft to neutral, at 73 to 82°F (23 to 28°C) with a pH of 6.0 to 7.5. Give it steady, well-oxygenated flow. Offer meaty foods at dusk, such as earthworms, prawn pieces, mussel and frozen bloodworm. Large eels are heavy feeders that quickly foul stale water, so keep conditions clean with regular changes.

Keep it as the only one of its kind, since it defends space against its own species. It ignores robust, mid-water tank mates its own size but will eat small fish. Choose large, calm companions rather than tiny or nippy ones. It has no known captive breeding record.

Good to know

The blackedge spiny eel, Mastacembelus nigromarginatus, belongs to the spiny eel family Mastacembelidae. It is one of the larger species in the hobby. George Boulenger described it in 1898 from West Africa. Like other big Mastacembelus, it carries small, deeply embedded scales. A long fringe of dorsal and anal soft rays runs behind the short spines that name the family. It is also called the nigromarginatus eel.

In the wild

The blackedge spiny eel lives in West African rivers of the Niger and Volta systems. It keeps to shaded margins with cover and current.

Common questions

What size tank does a blackedge spiny eel need?

A blackedge spiny eel needs at least 106 gal (400 L). It spends most of its time in the bottom.

What temperature and pH does a blackedge spiny eel need?

A blackedge spiny eel is comfortable at 73–82°F (23–28°C) with a pH of 6.0–7.5.

What does a blackedge spiny eel eat?

A blackedge spiny eel eats meaty foods at dusk, such as earthworms, prawn pieces, mussel and frozen bloodworm. It will also eat small fish.

How big does a blackedge spiny eel get?

An adult blackedge spiny eel reaches about 19.7 in (50 cm).

Related species