Hepper is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

6 Great Tank Mates for Fire Eels (With Pictures)

Lindsey Stanton Profile Picture

By Lindsey Stanton

Fire Eel in aquarium

While a Fire Eel is an excellent fish on its own, having a single fish in a tank can get a bit boring. Adding other species can make your aquarium more interesting and colorful, but what tank mates can you add to their enclosure that won’t cause any problems—or end up as lunch? Below, we’ll discuss the six best tank mates for Fire Eels and what you can expect from each one.

aquarium plant divider

The 6 Tank Mates for Fire Eels

1. Angelfish (Pterophyllum) — Easiest to Care For

Angelfish in aqurium
Image Credit: Piqsels
Size 6” long and 8” tall
Diet Tropical flakes, color flakes, tropical granules, and shrimp pellets
Minimum tank size 20 gallons
Care Level Low
Temperament Peaceful and timid

An Angelfish is one of the best tank mates you can get for your Fire Eel. Angelfish have a typically peaceful and timid temperament, and their larger size means the Fire Eel will not see them as food.

Keep in mind that Angelfish do best in schools, so you should consider getting at least six. Otherwise, they can get a bit temperamental and territorial. Finally, since Angelfish don’t require an overly large enclosure, the tank you have for your Fire Eel is likely already large enough.

2. Barb Fish (Barbus Barbus) — Most Variety

tinfoil barb fish
Image Credit: Zeyd Ladha, Pixabay
Size 3” to 13”
Diet Tropical flakes, color flakes, tropical granules, and shrimp pellets
Minimum tank size 30 gallons
Care Level Low
Temperament Playful but occasionally aggressive

Barb fish come in many varieties, which is part of the appeal of adding them as tank mates. However, finding the perfect Barb fish for your Fire Eel requires a bit of homework.

Too small of a fish and your Fire Eel will eat it, and too large of a fish and you’ll need a larger tank. These fish are known to be extremely playful but can have an occasional aggressive streak. That usually isn’t a problem with a Fire Eel companion, but it’s something to keep in mind if you’re adding other fish into the fray.

3. Silver Arowana (Osteoglossum Bicirrhosum) — Most Challenging Tank Mate

silver arowana in aquarium
Image Credit: Grigvovan, Shutterstock
Size 47”
Diet Earthworms, crab, crickets, shrimp, beef heart, krill, crustaceans, and feeder fish
Minimum tank size 250 gallons
Care Level High
Temperament Highly aggressive

Sometimes, you want a bit of a challenge, and when you do, the Silver Arowana is an excellent choice to pair with your Fire Eel. These massive fish can grow up to 4 feet long and require a tank of at least 250 gallons!

They’re also aggressive, so you can’t pair them with smaller fish. If you’re thinking of adding a Silver Arowana to your tank, ensure that you have enough space and can keep conditions and feedings ideal—otherwise, you might run into problems.

4. Oscar Fish (Astronotus Ocellatus)

white and orange oscar fish
Image Credit: Fabika, Shutterstock
Size 11″ to 12”
Diet Tropical flakes, color flakes, shrimp pellets, bloodworms, shrimp, boiled peas, and blanched spinach
Minimum tank size 55 gallons
Care Level Medium
Temperament Aggressive and territorial

A slightly challenging but popular fish to pair with your Fire Eel is the Oscar Fish. Just keep in mind that Oscar Fish are incredibly territorial, even with other Oscar Fish.

So, while a 55-gallon tank might be the minimum size, you might run into problems using anything smaller than 75 gallons. The more Oscar Fish you add, the larger tank you’ll need. Otherwise, they’ll fight and kill each other.

5. Green Terror (Andinoacara Rivulatus)

green terror cichlids
Image Credit: Piqsels
Size 8”
Diet Frozen krill, bloodworms, and brine shrimp; tropical flakes, plankton, green vegetables, cichlid pellets, or live red earthworms
Minimum tank size 75 gallons
Care Level Medium
Temperament Aggressive and territorial

An aggressive and territorial fish that pairs well with the Fire Eel is the Green Terror. Green Terrors can add a splash of bright color to your tank.

Due to this fish’s territorial nature, you need to ensure that you have a large enough tank, with a 75-gallon tank being a good starting point. The more fish you add, the larger the tank you’ll need.

6. Bichir Fish (Polypteridae)

Banded Bichir Fish
Image Credit: chonlasub woravichan, Shutterstock
Size 12” to 30”
Diet Shrimp, mussels, silversides, worms, and other live food
Minimum tank size 55 gallons
Care Level Medium
Temperament Occasionally aggressive

The Bichir Fish is an option that you need to do your research on before purchasing. Some Bichir Fish only reach 12 inches and are a great addition to a smaller tank.

However, they can grow 2.5 feet long, so if you get a larger Bichir Fish, you might need closer to a 100- or 150-gallon tank to fit them and a Fire Eel! Bichir Fish are primarily nocturnal, so you likely will not see them move around much during the day.

What Makes a Good Tank Mate for Fire Eel?

The most crucial factor when looking for a tank mate for your Fire Eel is the size of the tank mate. Fire Eels are natural predators, so you don’t want to pair them with smaller fish.

However, Fire Eels don’t disturb fish larger than them, and you don’t need to worry about them getting aggressive toward a large fish. It also means you can pair them with slightly more aggressive fish. Since the Fire Eel will leave them alone, the chances of them fighting with each other are relatively low.

Fire eel swimming inside the tank
Image Credit: Contentus, Shutterstock

Where Do Fire Eels Prefer to Live in the Aquarium?

Fire Eels are bottom feeders, and they spend most of their time at the bottom of the aquarium. They will search the bottom of the aquarium for food and burrow their way under the substrate throughout the day. They’ll often escape the notice of larger or more territorial fish.

Water Parameters

Caring for a Fire Eel is relatively easy. They’re freshwater fish that need temperatures between 75 and 82 degrees Fahrenheit. They’re incredibly sensitive to temperature changes, and you need a thermostat and a water heater to help you regulate the tank.

You can add plenty of other tank mates to the aquarium and focus some finer details around their needs because it won’t affect your Fire Eel.


The average Fire Eel will reach 3.3 feet in length, which is impressive for an aquarium fish! Therefore, you need a minimum tank size of 80 gallons to accommodate this beautiful fish.

Keep in mind that if you’re adding more fish, you’ll need to get an even larger tank, which can quickly drive up your costs.

Aggressive Behaviors

Most Fire Eels are docile unless you put them around their own kind. If you house more than one Fire Eel together, you need to have plenty of space and places to hide; otherwise, you’re asking for trouble.

Fire Eels need additional hiding spots if you’re adding other types of fish. This can be as simple as a loose substrate that they can burrow under or different objects inside the tank.

starfish 3 divider

The 2 Benefits of Having Tank Mates for Fire Eel in Your Aquarium

Adds more variety to the tank

While Fire Eels are interesting species, your tank will benefit from having more fish swimming around. Since these Eels sleep throughout most of the day, that means when you look at the tank, you probably won’t see much happening! Adding a tank mate changes the scenery and spices things up.

It gives them a more natural habitat

In the wild, Fire Eels aren’t the only fish around, so if you’re looking to replicate their natural habitat (and you should!), you should add different types of fish.

Just ensure you don’t overcrowd the tank since it won’t replicate their natural habitat and can harm the fish.

clos eup Fire eel open mouth inside the tank
Image Credit: Contentus, Shutterstock

Picking a Substrate for a Fire Eel

Fire Eels love to burrow, so you must account for two factors. First, the substrate needs to be a material that they can burrow into. Second, you need to avoid plants that grow into the substrate.

Ideally, you want about 2 to 3 inches of fine sand that won’t irritate your Fire Eel. If you want live plants, you need ones that float. Otherwise, your Fire Eel will quickly destroy anything that you plant.

To avoid learning an expensive lesson, be aware that live plants that grow in the substrate and Fire Eels aren’t a good mix.

aquarium plant divider


The good news is that if your Fire Eel has a large aquarium, there’s no reason that you can’t add a tank mate, and you have plenty of choices. Just ensure that the new tank mate won’t attack your Fire Eel and that they’re not small enough for your Fire Eel to eat!

If you hit both objectives, your Fire Eel will likely ignore their new companion, and you get another fish without the headache or price tag of a new tank!

See Also:

Featured Image Credit: Roberto Dani, Shutterstock

Related Articles

Further Reading

Vet Articles

Latest Vet Answers

The latest veterinarians' answers to questions from our database