Eyespot spiny eel

Care at a glance

Overview

Keep the eyespot spiny eel singly, as it is a solitary, territorial fish that does not share space with its own kind in a typical tank. It is a heavy-bodied burrower, so a deep, soft sand bed is essential; it lies buried through the day and comes out at night to forage. Peaceful toward larger fish, it will still eat anything small enough to fit in its mouth, so choose robust, calm tankmates rather than small tetras or shrimp. Feed chunky meaty foods such as earthworm, mussel, prawn, and the occasional strip of white fish. Because it grows large and produces waste to match, give it around 400 liters with strong filtration and a tight, weighted lid.

In the wild

The eyespot spiny eel comes from the Kapuas basin in western Borneo, in soft, tannin-stained forest rivers. Recreate that with a sand bed, driftwood, leaf litter, and dim, shaded lighting, and keep the water soft and slightly acidic. A pH around 5.5 to 7.0 and warm temperatures near 23 to 28 C suit it, and a handful of dried leaves or a little peat filtration helps hold the gentle blackwater character it prefers.

Good to know

Mastacembelus notophthalmus is a large spiny eel of the family Mastacembelidae, reaching roughly 45 centimeters. Its name comes from the Greek for back-eye, after the eye-like marking it carries high on the body, and 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. Aquarium spawning has not been recorded.

Did you know

The name notophthalmus means back-eye, for a false eyespot set high on the body; markings like this can draw a predator's strike away from the real head toward a part of the body the fish can better afford to lose.

Common questions

Related species

• Tin Win's spiny eel

  Mastacembelus tinwini

  Freshwater

  17.7 in (45 cm)106 gal (400 L)73–82°F (23–28°C)

• 

  White-spotted spiny eel

  Mastacembelus alboguttatus

  Freshwater

  19.3 in (49 cm)106 gal (400 L)73–82°F (23–28°C)

• 

  Marbled spiny eel

  Mastacembelus favus

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  19.7 in (50 cm)119 gal (450 L)75–82°F (24–28°C)
• Blackedge spiny eel

  Mastacembelus nigromarginatus

  Freshwater

  19.7 in (50 cm)106 gal (400 L)73–82°F (23–28°C)

• 

  Liberian spiny eel

  Mastacembelus liberiensis

  Freshwater

  15 in (38 cm)79 gal (300 L)73–82°F (23–28°C)
• Greshoff's spiny eel

  Mastacembelus greshoffi

  Freshwater

  15 in (38 cm)79 gal (300 L)73–82°F (23–28°C)