TankBud

Eyespot spiny eel

Mastacembelus notophthalmus

Also known as Notophthalmus eel, Black pearl eel

FreshwaterFish

Eyespot spiny eel (Mastacembelus notophthalmus)
(c) rukai95, some rights reserved (CC BY) · cc-by

Care at a glance

Temperature
73–82°F
23–28°C
pH
5.5–7.0
Adult size
17.7 in
45 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
Kapuas basin, Borneo

Overview

The eyespot spiny eel is a large spiny eel for a big, soft-water tank. It is a step up from beginner fish.

Did you know

The eyespot spiny eel's name, notophthalmus, comes from the Greek for back-eye. It refers to a false eyespot set high on the body. Such markings can draw a predator's strike away from the real head, toward a part the fish can better afford to lose.

Caring for the eyespot spiny eel

Give the eyespot spiny eel at least 106 gal (400 L), with strong filtration and a tight, weighted lid. It grows large and produces waste to match. It is a heavy-bodied burrower that lies buried through the day, so a deep, soft sand bed is essential. Add driftwood and leaf litter, and keep the lighting dim and shaded.

Keep the water soft and slightly acidic, at 73 to 82°F (23 to 28°C) with a pH of 5.5 to 7.0. A handful of dried leaves or a little peat filtration helps hold the gentle blackwater character it prefers. It comes out at night to forage. Feed chunky meaty foods such as earthworm, mussel and prawn, with the occasional strip of white fish.

Keep it singly, since it is a solitary, territorial fish that does not share space with its own kind in a typical tank. It is peaceful toward larger fish but will eat anything small enough to fit in its mouth. Choose robust, calm tank mates rather than small tetras or shrimp. Aquarium spawning has not been recorded.

Good to know

The eyespot spiny eel, Mastacembelus notophthalmus, belongs to the family Mastacembelidae. The trade sells it as the black pearl eel, for its dark, pale-flecked coloring. It has the family's embedded scales and long, finned tail. It is also called the notophthalmus eel.

In the wild

The eyespot spiny eel comes from the Kapuas basin in western Borneo. It lives in soft, tannin-stained forest rivers.

Common questions

What size tank does an eyespot spiny eel need?

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

What temperature and pH does an eyespot spiny eel need?

An eyespot spiny eel is comfortable at 73–82°F (23–28°C) with a pH of 5.5–7.0.

What does an eyespot spiny eel eat?

An eyespot spiny eel eats chunky meaty foods such as earthworm, mussel and prawn, with the occasional strip of white fish. It will also eat anything small enough to fit in its mouth.

How big does an eyespot spiny eel get?

An adult eyespot spiny eel reaches about 17.7 in (45 cm).

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