TankBud

Marbled spiny eel

Mastacembelus favus

Also known as Honeycomb spiny eel, Tyre-track eel, Favus spiny eel

FreshwaterFish

Marbled spiny eel (Mastacembelus favus)
The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature
75–82°F
24–28°C
pH
6.5–7.5
Adult size
19.7 in
50 cm
Minimum tank
119 gal
450 L
Temperament
Mostly peaceful
Social behavior
Solitary
Tankmates
With caution
Swim level
Bottom
Difficulty
Medium
Breeding
No record
Rarity
Common
Family
Mastacembelidae
Origin
Native to large rivers and floodplains of Southeast Asia, including the Mekong and Chao Phraya, over sand and among submerged wood.

Overview

This is a large spiny eel reaching about 50 cm or more, so provide at least 450 litres with a soft sand bed for burrowing and an absolutely sealed lid, as they escape readily. Keep it at 24 to 28 C and pH 6.5 to 7.5. It ignores fish too big to eat but will swallow small tankmates, so choose larger companions. Feed earthworms, prawns, mussel and other meaty foods after dark.

In the wild

The marbled spiny eel is a large, snake-like fish with a honeycomb pattern of pale rings over a dark body and a pointed, trunk-like snout. It burrows in sand by day and comes out at night to hunt. It is often confused in shops with the very similar tyre-track eel.

Good to know

Mastacembelus favus is frequently sold under the name of its close relative Mastacembelus armatus, but its pale markings extend down onto the belly and it stays a little smaller, at around 50 to 70 cm. Spiny eels carry a row of short, sharp dorsal spines. They are not true eels but members of the family Mastacembelidae.

Did you know

Because it is so often mislabelled as the tyre-track eel, many buyers only realise their fish is a different species once the belly markings give it away.

Common questions

What size tank does a Marbled spiny eel need?

A Marbled spiny eel needs at least 119 gal (450 L). It spends most of its time in the bottom.

What temperature and pH does a Marbled spiny eel need?

A Marbled spiny eel is comfortable at 75–82°F (24–28°C) with a pH of 6.5–7.5.

How big does a Marbled spiny eel get?

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

Related species