Fire Eel

Called an eel for its long, thin appearance, a Fire Eel actually isn’t a true eel at all. In fact, it is one of a species of elongated freshwater fish with pointy snouts known as spiny eels. These fish are popular aquarium pets because of their unusual color and size. These nocturnal, bottom-dwelling fish have long lives, both in the wild and as pets. Their price varies wildly depending on their size, from small to jumbo, so they can cost as little as $36 or have a price tag as high as $450, depending on size. Though they rarely bite, they can be a bit dangerous due to their spines and toxins, and the way they thrash around when captured.

5 Fire Eel facts

• Fire Eels reproduce by spawning.
• In the wild, a Fire Eel can reach lengths as long as a yard.
• Fire Eels are bottom-dwelling omnivores, but prefer meat.
• Male and female Fire Eels are difficult to differentiate, except during mating season, when the males get brighter, and the pregnant females get thicker.
• Female Fire Eels can lay up to 1,000 eggs per mating cycle.

Classification and Scientific Name

A Fire Eel is a type of spiny eel, which is not a true eel, but rather a kind of freshwater fish. Their scientific name is Mastacembelus erythrotaenia, of the Family Mastacembelidae in the Class Actinopterygii.

Appearance

Fire Eels are long, thin, and dark brown or gray with red or orange streaks or lines of spots up both their sides. In the wild, they can reach as long as 36 to 40 inches in length, while a pet Fire Eel in a tank may only grow up to be about 20 inches in length. They have no abdominal fins, but they have somewhat dangerous spines along their dorsal fins. Males and females are very nearly identical, except when a female is pregnant and about to lay eggs, at which time she is bulkier than her male counterparts.

Distribution, Population, and Habitat

Fire Eels can be found throughout Southeast Asia, including Indonesia , Laos , Vietnam , Cambodia , Pakistan , Burma , Thailand , and Malaysia . They are usually found in rivers that move more slowly because those bodies of water tend to have muddier bottoms, and Fire Eels love to burrow in the mud. Though they are somewhat overfished in places where the aquarium trade is more common, they are considered of least concern, according to the IUCN Red List (assessed in 2025), and are common throughout the region.

Predators and Prey

Fire eels have few natural predators, due to the toxic slime they secrete and the sharp spines on the dorsal fins. They are omnivorous bottom feeders that eat very small fish, crustaceans, invertebrates, plant matter, and sometimes even detritus.

Reproduction and Lifespan

A Fire Eel in the wild can live up to 15 years, with a 20-year expected lifespan in a tank. Fire eels mate by spawning. This means when Fire Eels reach mating season and sexual maturity, the colors on the males brighten. When he finds a female, he “mates” by squeezing her to make her release her eggs, which he then fertilizes externally. She may lay as many as 1,000 total eggs. The eggs will hatch in only a few days, and the fry will live off the yolk as their first few meals.

Fire Eel in fishing and cooking

Though they are used in cooking in some parts of the world, Fire Eels are more commonly found in tanks than on plates.