Frecklefin spiny eel

Care at a glance

Overview

Keep the frecklefin spiny eel on its own, since it lives alone in the wild and tolerates its own kind poorly in the confines of a tank. It is a bottom fish that buries in sand by day and patrols the floor and glass line after dark, so soft sand and shaded hides are the priorities. It is gentle with tankmates it cannot swallow but will eat small fish, so pair it with calm, medium-sized species and avoid tiny or nervous ones. Feed meaty foods such as frozen bloodworm, blackworm, chopped earthworm, and small prawn pieces, dropped near the substrate at dusk. A tank of about 250 liters with fine sand and a close-fitting lid suits it.

In the wild

The frecklefin spiny eel lives in shaded lowland forest streams across Sundaland, in Malaysia and Indonesia, where the water is soft and acidic under a leafy canopy, with beds of litter and submerged plants. Match that with a sand base, driftwood, dried leaves, and subdued light. It does best in soft water with a pH around 5.5 to 7.0 and warm temperatures near 23 to 28 C, with gentle flow and plenty of low cover to retreat into.

Good to know

Macrognathus maculatus, the frecklefin eel of the family Mastacembelidae, reaches about 28 centimeters. Its name means spotted, for the freckling scattered along its fins and flanks. In the wild it feeds on insect larvae, worms, and small crustaceans lifted from the substrate with its mobile snout. Like most of the family it has no documented aquarium breeding record.

Did you know

Despite the shape and the name, spiny eels are not true eels at all: they sit in the order Synbranchiformes alongside the swamp eels, and the short spines set before the dorsal fin, which real eels lack, are what mark the family out.

Common questions

Related species

• 

  Peacock Spiny Eel

  Macrognathus siamensis

  Freshwater

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

• 

  Zebra spiny eel

  Macrognathus zebrinus

  Freshwater

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

• 

  Mae Klong spiny eel

  Macrognathus meklongensis

  Freshwater

  9.8 in (25 cm)70 gal (265 L)73–82°F (23–28°C)
• Half-ocellated spiny eel

  Macrognathus semiocellatus

  Freshwater

  9.1 in (23 cm)53 gal (200 L)73–82°F (23–28°C)
• Burmese spiny eel

  Macrognathus orthosemos

  Freshwater

  8.7 in (22 cm)53 gal (200 L)73–82°F (23–28°C)
• Line-spot spiny eel

  Macrognathus lineatomaculatus

  Freshwater

  8.7 in (22 cm)53 gal (200 L)73–82°F (23–28°C)