Fire eel (Mastacembelus erythrotaenia) resembles a true eel, that’s why the fish got its name. However, this fish has nothing in common with eels despite its snake like body and pointed snout. This is a renown tank and commercial fish.
Habitat in the wild
Mastacembelus erythrotaenia dwells in waters of Indonesia, Laos, Vietnam, Cambodia, Pakistan, Burma, Thailand, Malaysia and other countries of South-East Asia. This bottom-dwelling fish is mainly encountered in slow muddy rivers and lakes, since one of its favorite activities is to bury itself in the riverbed.
In Asia locals eat fire eel, therefore it is highly prized among them. However, young fishermen and aquarists don’t share this attitude because of troubles fire eel gave them with its spines on the dorsal fin.
When being caught the fish tries to escape as fast as possible and it may hurt the one who is holding it with its spines.
Spines themselves are not poisoned, but the slime they produce is toxic. So, if a fire eel has bitten you, hurry up and apply some antiseptic to the wound. But still it is better to be careful with this fish and not to touch it.
Mastacembelus erythrotaenia appearance is like the one of eel. Its elongated body is covered with small scales. The fish has big eyes. Near the anterior border of the fish eye there are its posterior nostrils.
When looking for food fire eel feels the bottom with a sensitive fleshy outgrowth on its snout. At the end of this long nose appendage there are two tubulated nostrils. Due to this peculiarity fire eel is referred to Mastacembelidae family.
The fish has well developed air-bladder as well as tail and pectoral fins. The dorsal is divided into two parts. Both anal and dorsal fins are narrow and long and they end near caudal fin.
Fire eel has no abdominal fins. The fish coloring is dark brown. There are four bright red or orange lateral stripes along the fish body, very often they consist of spots and small lines. The color intensity of the spots varies depending of the fish age and tank conditions. As a rule anal, dorsal and pectoral fins have red edges.
In the wild fire eel body length may reach 1 m (3.3 ft), when dwelling in a tank it is 0,5 meters (20 in) long. The fish lifespan is 10 years and more.
Difficulties in keeping
The fish is rather undemanding, but the fact that this is a predator fish and a large one as well imposes restrictions on keeping it in a tank. You will need at least very spacious tank with tankmates that are large enough, so the fish won’t treat them as food.
Keeping in a tank
|Scientific Name||Mastacembelus erythrotaenia|
|Common Name||Fire eel|
|Tank size||77 gallons and more|
|Diet||Omnivorous bottom feeder|
|Size||up to 1 m (3.3 ft)|
To keep one adult species of the fish you will need a tank larger than 350 liters (77 gallons), with 5 cm (2 in) thick sandy bottom and large number of shelters made of snags, flower pots, bunches of coarse leaved and floating tank plants, that will make the bottom a bit shadowed.
Fire eel adores hiding.
It is likely that you’ll have to forget about tank plants with roots and replace them with floating ones, because fire eel when burying itself in a sandy bottom doesn’t care about about the place, so it is quite possible that the fish will dig some tank plant roots and damage them.
This fish is a nocturnal one. During the day it hides under snags and stones, buries itself in the tank bottom substrate and all you can see is its eyes and a snout.
You should make sure that there are no cracks in the tank, otherwise fire eel will easily ‘escape’ from the tank through the tiniest slit.
Since the fish demonstrates aggression towards its kind, you should keep it alone in a tank but it may have a company of some active and peaceful tank fishes.
Optimal tank water parameters are the following: temperature 24-28°С (75-82°F), рН 6.8-7.5, water hardness should be not more than 15°. Power aeration, filtration and regular water renew (up to quarter of the total tank volume) is a must when keeping such a fish. It also likes when there is some water flow in a tank.
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