Family: Synbranchidae
An air-breathing eel from China and Southeast Asia. Burrows by day, hunts by night — keep alone in a soft-substrate, covered tank.
A Synbranchidae species native to China, Southeast Asia: Monopterus albus lives bottom; rests and forages low over clear streams, rivers and still waters. Solitary nocturnal predator — keep alone. Adults reach 70–100 cm.
No — true eels belong to a different order entirely. The swamp eel is a synbranchiform fish, more closely related to spiny eels and swamp-dwellers of several independent lineages.
It is nocturnal and fossorial — a burrower by design. Provide feeding opportunities after lights-out and be patient; forcing constant visibility causes stress.
Yes. It is a sequential hermaphrodite, maturing first as female and transforming into male as it grows large. Age and size, not social cues, drive the change.
Only large, fast fish it cannot swallow; anything smaller becomes food eventually, including slow tankmates at night.
Yes, but treat it as an advanced project, not a pet fish. Monopterus albus is an air-breathing nocturnal predator reaching 70–100 cm. It needs 1,000 L+, a soft substrate it can burrow into, a truly escape-proof lid, and a tank of its own. It spends daylight hours buried and shows little interactive behavior.
Not for breathing — they gulp air at the surface and can survive hours out of water in damp conditions. But you still want filtration and gentle aeration for water quality. Deteriorating water is what actually kills them: foul conditions trigger fasting and fungus.
That's completely normal. It's a strict nocturnal burrower that spends daylight hours under sand or inside rock crevices and only patrols at dusk. Dim the lights, feed after dark, and use dark fine sand if you want to see more of it — it will never cruise openly like a goldfish.
Strict carnivore: loaches, shrimp, small fish, bloodworms. Pellet training takes patience — skip feeding for a few days, then wiggle live food with tweezers at the burrow entrance, gradually mixing in sinking carnivore pellets. Freshly wild-caught eels usually need a week of dark, quiet acclimation first.
No. It will bite and consume anything it can swallow — resting koi lose fins overnight — and turtles will shred it. House it alone; even tankmates too large to eat will harass it. Solitary housing is the only workable setup.
It's a legendary escape artist. Swamp eels can crawl across damp surfaces for surprising distances, and any uncovered gap — filter intakes, heater cord cutouts — is an exit. A tight custom mesh lid with every opening foamed shut is non-negotiable, or you'll find a dried eel on the floor.