Like the Monty Python comedy troupe used to say, “And now for something completely different.”
Looking for something that little bit different for your freshwater aquarium setup?
Most hobbyists know the benefits of having fish alongside species like snails or invertebrates like shrimp.
Maybe you have dabbled with a dwarf frog or even a turtle or two.
But for something truly unique in the hobby, why not consider something like an eel?
Eels have that ancient, prehistoric look. There is a wide variety you can choose from, and there’s one to suit all. You just need to know which species will work for you and do your homework. Other than that, an eel can make a captivating addition to a tank community or work equally well on its own.
Within the Order Anguilliformes that all eels belong to, there are over 800 types overall across all water types.
They can be found just about anywhere in the world, from tropical to temperate climes, which means they are a very diverse group.
This article will take a look at the most popular Freshwater Eels (Order Anguilliformes) for aquariums to help you decide which might suit you best. We will cover the general ways you need to care for them in brief, but if you pick one, we recommend doing additional research as this is an overview to help you decide.
Some species are not well suited to the hobbyist at all, and others should be only taken on by experienced ones. Others are perfectly suited to even the novice. We will take a look at a wide range of species today.
Another point to note here is that all Freshwater Eels are technically ‘fish.’ There are other species that are legless amphibians that resemble eels but are not truly an eel, and they belong to another Order or Family.
True eels are marine versions that have a very complex life cycle and are never found in freshwater for life. Even so-called Freshwater Eels return to brackish or marine habitats to breed.
Shall we slither into this exciting category of options for the fish-keeping hobby? Let’s go!
Popular Types Of Freshwater Eels
Fire Eel
These eels are really pretty. They have dark bodies punctuated by vibrant flashes of orange, red, and yellow, which is exactly how they got their name.
They are a spiny eel variety and can grow up to 40 inches long in captivity, so rather large, and this would need to factor into your tank size requirements.
These eels are compatible with other non-aggressive fish, but you should not keep them with another of their kind; aggression is likely to ensue.
Fire Eels are bottom dwellers who like to bury themselves in soft, smooth gravel or sandy substrates so take that into account if you already have other bottom-dwellers. Nobody wants a crowd on the floor!
These larger eels do still like a place to hide and seek, and tubes make a great addition to the tank along with driftwood and suitable plantlike that can survive lower lighting conditions.
Floating plants suit them best. Playful and friendly fish, these eels can even be hand-fed by their owners as they will recognize you over time.
As they do live a long time, they are best suited to experienced owners only, and they will need a huge tank upwards of 180+ gallons for an adult.
Water specifications:
- pH 6.5 – 8
- 5 – 15 dGH
- Temperature 73 – 82ºF
Tire Track Eel
The Tire Track Eel has a pattern that resembles, you guessed it, a tire track that zigzags along the length of their body.
Growing up to 30 inches in length at full maturity, they require a sizeable tank.
These eels enjoy hiding and will burrow in the sand as many other eels do. Including some interesting decor in your landscape will help them feel secure and encourage them to come out to play. Tubes, caves, and rocks to hide around will help enormously for these shy types.
They are quiet and don’t get involved with other fish too much, and are not aggressive, preferring a sedentary lifestyle.
Tire Track Eels can be kept in a pair but ideally bought at the same time, as newcomers can bear the brunt of some aggression once they have established themselves in the tank. Avoid keeping smaller fish species alongside them as they will be eaten as food with pleasure.
Again, floating plants are best, along with dim lighting settings.
Water specifications:
- pH 6.5 – 8
- 5 – 15 dGH
- Temperature 73 – 82ºF
Peacock Eel
With a grand-sounding name like Peacock, you would expect these eels to be large. In fact, they are rather small and manage to reach 12 inches at full maturity.
They have thick black horizontal striping along the length of their bodies and then, in the final quarter, have circular black spots along the topline only.
This makes them a great option for people who have a much smaller amount of space who still want to tell the world they have an eel as a pet.
They also happen to be ‘true’ eels, so you might earn some bragging rights amongst the community if you decide to get them.
Again, they burrow into soft sand or smoother rounded substrates during the day and then hunt at night. High oxygenation in your tank is a must, and they are recommended for intermediate or experienced hobbyists for that reason.
Canister filters of substrate filtration systems work well for them along with additional air stones or even air curtains as long as the water flow isn’t too strong. Lids are needed, too, or you may find yourself with an unexpected escapee!
You can handle adult Peacocks with a minimum of 55 gallons and upwards for a single one.
Water specifications:
- pH 6.5 – 7.5
- 5 – 15 dGH
- Temperature 73 – 80ºF
Asian Swamp Eel
If you’re looking for an eel to make a huge impression, this might be the eel for you. We say huge because you will need a massive tank to be able to show one of these off.
180+ gallons of space, which is not achievable for the average hobbyist. These eels are most certainly in the category of expert fish-keeping range. Their tanks must also be longer as opposed to deep as they need to stretch out as they swim, so this is another space consideration.
Certainly not for the faint of heart, these eels are aggressive and can bite and kill tank mates as juveniles, so they must be kept solo. It’s possible to keep a few of them together with their own kind, but best to avoid other species overall unless you have space for fish at least 12 inches in length which can stand up for themselves.
A word of warning, they have very strong jaws, so handling one is best left to experts as they can latch on and cause some serious damage!
Asian Swamp Eels do like other eels do, which is burrow, hide in tubes, as well as active full-length laps of the tank.
They have been used for food supply in the past and are now considered an invasive species in North America after release into the wild.
Water specifications:
- pH 6.2 – 8.0
- 5 – 25 dGH
- Temperature 78 – 82ºF
Electric Eel
Electric eels are among the most expensive and probably with good reason. They should only be handled and cared for by the most experienced hobbyists, so the price may inhibit amateurs from getting one and causing undue havoc.
It’s a huge eel too. They can reach 60 – 80 inches in length, produce large quantities of electricity (up to 500 Volts) and stun inexperienced owners with a shock. Handle with care and consider one only if you are fully equipped to deal with one!
They have a plain dark grey body, but it’s their name that makes them popular for the true aquarist with loads of experience looking for a claim to fame. Everyone knows this species and the danger associated with them means they might even make their owner feel like a real Bond villain.
If this is you, and you really, really want one, you will need a gargantuan 200-gallon tank minimum to accommodate it.
But since you’re probably on the verge of Bond villain status, surely you have the size, space, and money to just go out and get one!
Rubber Eel
Here we have one of those legless amphibian types we mentioned at the start. With dark coloring, they can occasionally be seen breathing air at the surface because of their amphibious nature.
If you’re looking for one of the easiest ‘eels’ to have in your setup, these just might be it.
Requiring a moderate tank size of 55+ gallons for adults and reaching a reasonable 22 inches in length, they might just be the easiest for beginners, even if it isn’t a true eel.
They are not bothered by other tank mates and are nearly fully blind.
Again, a fine and soft substrate is ideal as these guys will burrow and have a slime coating. Take care to mingle Rubber Eels with smaller fish that don’t eat slime coats to keep them from being harassed and distressed by nibblers.
Water specifications:
- pH 6.5 – 7.2
- 5 – 15 dGH
- Temperature 78 – 82ºF
Other Types Of Freshwater Eels For Aquariums
There are other eels and eel-like species that hobbyists successfully keep, which include:
- Pink Paddletail Eels
- Starlight Spiny Eels
- Spaghetti Eels
- American Eels
- European Eels
- Black Spotted Eels
- African Spiny Eels
Most require the same types of tank setup and parameters as those we detailed in more depth above, but please do check and research thoroughly as required for your specific species.
How To Feed Freshwater Eels
All eels are carnivores and are happy eating dry and live or frozen foods, but they should not be fed flakes or pellets.
You could feed crustaceans like micro crabs and shrimp, small live feeder fish, and worms. Frozen or live will work, but do try to feed them a degree of live foods for optimum health.
There are specialized sinking pellets made specifically for eels but check with the supplier if they are suitable for your species.
Common Health Issues
Water quality is paramount to keeping freshwater eels healthy. With most having slime coatings, they are highly prone to infectious diseases more readily than their scaly counterparts.
They need high oxygenation, so using live plants will help with this, and we already recommended that you chose floating varieties since they will almost certainly burrow.
Good options include Java Moss and Hornwort to help aerate the tank.
Change the water weekly and at least 30% because these guys are usually large and create a lot of waste. Failure to do so will cause problems, and quickly, as ammonia and nitrites will spike rapidly if you don’t, and they are incredibly sensitive to that.
Fungal, parasitic, and bacterial infections are all on the cards if you host eels, so particular zeal for tank cleanliness needs to be in your nature if you choose to have any and keep them with any degree of longevity.
Are Freshwater Eels A Good Idea For Your Aquarium?
Would an eel electrify your tank as a hobbyist? On that note, we hope that if it’s that species that it’s the only one in the tank!
But for some of the smaller species, we listed here, they would surely make a fascinating addition provided you have the relevant experience and space required to make their world a healthy one.
Their unusual swimming action, snake-like moves, and unique patterns for some species do make them a really attractive goal for an aquarist with a deep enough pocket to have the space.
Eels do best with larger peaceful fish, so you don’t necessarily have to have an eels-only tank. They do make a really interesting option depending on the species you wish to keep alongside them for that extra-special bit of difference. And what a talking point they make, too!
For anyone aiming to house those really big ones, we salute you – and make sure you have a lid!
