TankBud

Half-banded spiny eel

Macrognathus circumcinctus

Also known as Zig Zag Eel, Striped-belly spiny eel, Taeniagaster spiny eel, Macrognathus taeniagaster

FreshwaterFish

Half-banded spiny eel (Macrognathus circumcinctus)
The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature
75–81°F
24–27°C
pH
6.0–7.5
Adult size
7.9 in
20 cm
Minimum tank
57 gal
215 L
Temperament
Mostly peaceful
Social behavior
Solitary
Tankmates
With caution
Swim level
Bottom
Diet
Carnivore
Difficulty
Medium
Breeding
No record
Rarity
Very rare
Family
Mastacembelidae
Origin
Sumatra, Malaysia, Thailand

Overview

The half-banded spiny eel is a small, secretive spiny eel that is active at night. It is a step up from the easiest fish.

Did you know

The half-banded spiny eel burrows into soft sand and rests through the day with just its snout poking out.

Caring for the half-banded spiny eel

Give the half-banded spiny eel at least 57 gal (215 L) and a deep bed of soft, fine sand to burrow into. Sharp gravel scratches its scaleless skin and can lead to serious infections. Add gentle flow and hiding places among wood and plants. It can slip through small gaps, so fit a tight lid.

Keep the water slightly acidic to neutral, at a pH of 6.0 to 7.5 and 75 to 81°F (24 to 27°C). Feed live and frozen foods such as bloodworms, blackworms and small shrimp after dark.

Keep it singly, with calm tank mates that are too big to be swallowed but not aggressive enough to bully it. Breeding in home aquariums is rarely recorded.

Good to know

The half-banded spiny eel, Macrognathus circumcinctus, belongs to Mastacembelidae, the spiny eel family. It is named for the row of dark bars that reach only halfway down its flanks. The small spines set ahead of its dorsal fin give it the rest of its name. Like other spiny eels, it has a long, flexible body and a fleshy, trunk-like snout it uses to probe the substrate. In most aquariums it stays smaller than its full adult size.

In the wild

The half-banded spiny eel comes from Southeast Asia, in the slow rivers, floodplains, canals and vegetated margins of Sumatra, Malaysia and Thailand. The bottom there is soft mud or sand, and cover is plentiful.

Common questions

What size tank does a half-banded spiny eel need?

A half-banded spiny eel needs at least 57 gal (215 L). It spends most of its time in the bottom.

What temperature and pH does a half-banded spiny eel need?

A half-banded spiny eel is comfortable at 75–81°F (24–27°C) with a pH of 6.0–7.5.

What does a half-banded spiny eel eat?

A half-banded spiny eel eats live and frozen foods such as bloodworms, blackworms and small shrimp. Feed it after dark.

How big does a half-banded spiny eel get?

An adult half-banded spiny eel reaches about 7.9 in (20 cm).

Related species