Half-banded spiny eel

Care at a glance

Overview

This small spiny eel is a secretive, night-active fish that spends the day buried in the sand with only its snout showing. It must have a soft sand bed it can burrow into, since sharp gravel scratches its scaleless skin and invites infection. Keep it singly with calm tankmates that are too big to be swallowed but not aggressive enough to bully it. Feed live and frozen foods such as bloodworms, blackworms, and small shrimp after dark. It can slip through small gaps, so fit a tight lid. Give it a tank of at least 215 liters.

In the wild

Macrognathus circumcinctus comes from Southeast Asia, in the slow rivers, floodplains, canals, and vegetated margins of Sumatra, Malaysia, and Thailand, where the bottom is soft mud or sand and cover is plentiful. Recreate this with a deep bed of fine sand, gentle flow, and hiding places among wood and plants. Keep the temperature between 24 and 27 degrees Celsius and the pH slightly acidic to neutral, from about 6 to 7.5.

Good to know

The half-banded spiny eel belongs to Mastacembelidae, the spiny eel family, and reaches about 20 centimeters, staying smaller in most aquariums. It is named for the row of dark bars that reach only halfway down its flanks, and for the small spines set ahead of its dorsal fin. Like other spiny eels it has a long, flexible body and a fleshy, trunk-like snout it uses to probe the substrate. Breeding in home aquariums is rarely recorded.

Did you know

The half-banded spiny eel burrows into soft sand and rests through the day with just its snout poking out. A tank with sharp gravel instead of sand can scrape its bare skin and lead to serious infections.

Related species

• 

  Peacock Spiny Eel

  Macrognathus siamensis

  11.8 in (30 cm)70 gal (265 L)75–82°F (24–28°C)
• Zebra spiny eel

  Macrognathus zebrinus

  11.8 in (30 cm)42 gal (160 L)72–81°F (22–27°C)
• Lesser spiny eel

  Macrognathus aculeatus

  15 in (38 cm)85 gal (320 L)73–82°F (23–28°C)
• Marbled spiny eel

  Mastacembelus favus

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

• 

  Tire-track eel

  Mastacembelus armatus

  27.6 in (70 cm)119 gal (450 L)75–82°F (24–28°C)

• 

  Fire eel

  Mastacembelus erythrotaenia

  39.4 in (100 cm)132 gal (500 L)75–82°F (24–28°C)