Fire eel

Mastacembelus erythrotaenia, the fire eel, is a large spiny eel in the family Mastacembelidae, native to slow rivers, floodplains, and lakes of Southeast Asia. Despite the name it is a true fish, with an elongated body, a fleshy pointed snout, and dark brown to black coloration marked by bright red or orange lateral stripes and spots. It is largely nocturnal and secretive, spending daylight hours burrowed in soft substrate. Adults can be territorial toward their own kind but generally ignore fish too large to swallow, so tankmates should be sizeable and peaceful. Because it grows very large, it requires a spacious aquarium with a soft sand bottom for burrowing, sturdy hiding places, and secure covers, as it is a determined escape artist. Feeding centers on meaty foods such as earthworms, bloodworms, and pieces of fish or shrimp; many specimens must be weaned onto prepared foods.