Moray Eels are unusual fish right off the bat. But even within their family there are odder cousins. The Ribbon Eel is a strange fish that catches your eye right away. When swimming they seem unearthly in how they move. And when peering from rocks they boldly glare right back, ready to bite if you get too close. Have you ever considered caring for Ribbon Eels?
What are Ribbon Eels?
Ribbon Eels are easily some of the most unusual fish you’ll ever see. They are very long, extremely thin true eels that are true Morays but are distinct enough to possibly merit their own family.
Like all Morays Ribbon Eels have a highly acute sense of smell but their nostrils are flared outwards almost like a Chinese Dragon. They also have a habit of keeping their mouths constantly gaping far wider than other Morays and even when free swimming.
Ribbon Eels are also one of the many saltwater fish that go through sex changes as they mature. You will often see them labeled as Black, Blue, or Yellow Ribbon Eels. Each color actually corresponds to a different sex rather than a different species!
There’s quite a bit to learn about Ribbon Eels, so let’s dive right in!
- Common Names: (Blue/Black/Yellow) Ribbon Eel, Leaf-Nosed Moray Eel
- Scientific Name: Rhinomuraena quaesita
- Origin: IndoPacific
- Length: 3-4 feet
- Aquarium Size: 55-75 Gallons
- Temperament: Aggressive
- Ease of Care: Difficult
Caring for Ribbon Eels
Given how difficult they are to feed, their need for pristine water quality, and strong territorial instincts, Ribbon Eels are for experienced aquarists only.
Aquarium Size
Ribbon Eels are rather unusual in that they are immensely long but also crazy thin. When you see one free swimming they truly live up to their name. Fortunately, their bioload isn’t as high as any other fish their length and they spend most of their time tucked away into their lairs.
A single Ribbon Eel can live in an aquarium as small as 55 gallons. If kept with other fish, especially other Ribbon Eels, I recommend upping the space to 75 gallons-90 gallons.
Water Conditions
Ribbon Eels don’t need much in the way of unusual water parameters but they are highly intolerant of poor water quality. Temperatures should remain between 72-82℉ and remain stable over the long term. The pH should be between 8.1-8.4 and the salinity anywhere between 1.020-1.025.
What’s much more important is keeping concentrations of ammonia, nitrite, and nitrate as close to 0ppm as possible. This can be quite challenging because Ribbon Eels are predators that eat a lot when they decide to eat at all.
A high powered canister filter is essential for the Ribbon Eel tank. They provide you with the biological, mechanical, and chemical filtration power you need to keep the water pristine. The high water turnover rate also improves oxygenation.
Aquascaping for Ribbon Eels
There are two major concerns when aquascaping with Ribbon Eels in mind: seclusion and security. They absolutely need a hideaway to retire within. But oftentimes, and especially at night, they will wander about, testing your lid and every other way of escaping the tank.
And given how slick and thin they are, they can squeeze through holes as small as an inch in diameter with ease. You can’t be complacent when setting up a tank for a Ribbon Eel because it will end up on the floor eventually otherwise.
They aren’t quite as strong as larger Moray Eels when it comes to lifting tank lids. But you’re still better off securing it with a clip or even a rock!
Provide your Ribbon Eels with a variety of places to choose from. They love threading themselves in between chunks of coral and live rock so leave plenty of hidden space for them to wander through.
They also love the dark, tight confines of PVC piping and other artificial caves. A Ribbon Eel with several secure caves to choose from will settle in faster and eat sooner than one stressed without a refuge.
When placing each block of live rock you’ll definitely want to fasten it in place with some epoxy because Ribbon Eels are definitely strong enough to dislodge pieces, sometimes with fatal consequences.
Scaleless fish are particularly susceptible to infections when their skin is damaged. And healing them can be a real challenge because the lack of scales makes them much more sensitive to medications than the standard dose usually recommends.
Tank Mates for Ribbon Eels
Choosing tank mates for any Moray Eel species is a challenge and Ribbon Eels are no exception. Given how thin and small they are (for Eels) you’ll have a somewhat easier time of things.
Like all Morays, Ribbon Eels are extremely territorial when it comes to their hiding hole. They will snap at any fish that tries to push its way in or even gets too close. Their teeth are needle sharp and capable of inflicting a fatal bite on an unwary fish.
That said, most fish that are too large to be eaten and aren’t looking to explore caves are safe when kept alongside a Ribbon Eel. Deep bodied fish are the best choices. Rabbitfish, Tangs, Angelfish, larger Clownfish and Damselfish can all work. But watch out for aggressive species such as Maroon Clownfish and Domino Damselfish. Ribbon Eels don’t tolerate bullying well and stress easily.
Other predatory fish can also work, such as Lionfish, Groupers, and other Moray Eels. But you’ll need to be extremely cautious because as thin as Ribbon Eels are, other predators may try to eat them.
Other Moray Eels are the best choice so long as you provide plenty of hiding places for everyone and don’t choose species that are too large. But even smaller species, such as the Snowflake Moray (Echidna nebulosa) may try to snap at or even eat a smaller Ribbon Eel.
Ribbon Eels are also quite sociable and prefer being kept in groups. In fact, groups of eels tend to have a much better appetite and help explain why they are so difficult to feed as single specimens in home aquariums.
Ribbon Eels are actually safe with corals, anemones, and nearly all invertebrates. The smallest of shrimp species may trigger a feeding response. But larger shrimp should be safe since these eels strongly prefer eating fish.
Your Ribbon Eel may disturb some corals if they are placed too close to its favorite hiding places. They should be moved to a different area to avoid stressing the polyps. And considering the predatory diet of Ribbon Eels they do release copious amounts of waste that can impact water quality. But many soft corals, including Pulsing Xenia and Green Star Polyps, thrive on the leftover organic matter.
Good Tank Mates for Ribbon Eels
- Angelfish, Tangs, Rabbitfish, Groupers, Lionfish, and other deep-bodied community fish
- Other Ribbon Eels
- Moray Eels (with caution)
- Most Corals and Invertebrates
Poor Tank Mates for Ribbon Eels
- Small Clownfish, Damselfish, Gobies, Firefish, Cardinalfish, and other fish small enough to be eaten
- Small Shrimp
Feeding Ribbon Eels
By far the most challenging aspect to Ribbon Eel care is getting them to eat. Newly imported eels are famously difficult to get eating. They will often fast for weeks and may even starve to death despite you offering them all sorts of prey items.
The main reasons Ribbon Eels fail to eat in captivity are stress from transport and offering the wrong kinds of food. It’s suspected that cyanide capture may be part of the reason why they fail to eat and die.
In many parts of the world cyanide is used to stun fish in order to make them simple to catch. Ribbon Eels live in coral grottos and are next to impossible to catch without somehow forcing them from their holes. The problem with cyanide is that it’s just as lethal to fish as it is to humans – it just takes longer to become fatal at the doses used.
Over the course of weeks to months many cyanide collected fish never recover, stop eating, and waste away. Since they’ve usually made it to their final aquarium home by this point so the collectors have no reason to care.
Another reason Ribbon Eels fail to eat is that they are dedicated predators (piscivores – fish eaters) and almost always fail to wean onto dead prey. Even offering them food on feeding sticks may not always work like it does for other Moray Eels. They are extremely picky and prefer snatching living fish from the water column.
And even if you offer live fish there’s still no guarantee that they will eat. Ribbon Eels are simply sensitive fish that even expert aquarists struggle with. A few strategies aquarists have used live Rosy Reds, Goldfish, and even small Damselfish, and found they trigger a better feeding response due to their bright colors. Scale the size of your feeder fish appropriately: Guppies may be best for baby Ribbon Eels.
Mollies are the best bang for your buck – while they are usually sold as freshwater fish they are actually capable of transitioning to full seawater. Keeping a colony of Mollies in a hanging refugium can ensure you have a constant supply of live prey for your Ribbon Eel. Try buying several different colors (especially Gold Dust Mollies) to see which triggers the best response from your Eel.
Raising Mollies also helps cut down on the chance of parasites infecting your Moray Eel. Standard feeder fish are notoriously laded with infestations that they can easily transmit to their predator.
Once (if) you’ve got your Ribbon Eel eating live prey you might then try to transition it onto dead prey. But don’t push if they don’t go for it as they will outlast you on a hunger strike and may not come out of it.
Marine fish are ideal for them. Smelt soaked in garlic or other nutrient additives may work with a bit of luck. The garlic soak appeals to the Ribbon Eel’s highly sensitive sense of smell and triggers a robust feeding response.
You’ll likely always need to simulate the movements of live prey, though. Use your feeding tongs to wiggle the food back and forth. And make sure each Eel gets fed if you’re keeping more than one Ribbon Eel as they will fight viciously for food.
As you’ll see comparing the above video to the prior one, their feeding response is haphazard at best. They may be master predators at times, snatching live fish with ease. And other times they fail to even notice food when it hits them in the face. You just have to be prepared for weirdness when feeding Ribbon Eels.
Once you have them eating, they are eager feeders. Ribbon Eels can be offered one fish per day at this point!
A final point: Ribbon Eels are quite sociable; groups of them almost always do better in aquariums than eels kept singly. If you’re going to keep one, you might be much better off buying two or three. They will share caves and when one eats the others take immediate interest!
Breeding Ribbon Eels
Breeding Ribbon Eels is mostly a matter of luck due to their unwillingness to feed in most aquariums and their habit of escaping and ending up dead. And considering how pricey and delicate they are few aquarists end up buying several at once.
That said, they are actually very reliable to sex because Ribbon Eels go through dramatic color changes as they mature. Juvenile Ribbon Eels are a deep black in color and are often sold as Black Ribbon Eels. But each color label refers to a stage in their development rather than a different species.
“Blue” Ribbon Eels are actually mature males. But it gets much more interesting than that: Ribbon Eels are protandric hermaphrodites. This means that the eels change sex as they mature. In this case, the juveniles start out as males and as they close in on their final size they become “Yellow” Ribbon Eels, which are mature females!
The process is slightly more complicated as the few times Ribbon Eels have been observed breeding in captivity the colors have reversed. Sometimes the pair reverts entirely to black. But it’s fairly safe to assume that you have a male if it’s blue and a female if larger and yellow in color. Like many hermaphroditic fish its likely Ribbon Eels can also change sex due to social dynamics.
Once you have your “harem” of Ribbon Eels it’s entirely a matter of luck at this point since it’s not known what foods, temperatures, or other environmental cues trigger spawning. A few lucky aquarists have found masses of floating eggs laid by the eels.
But they otherwise provide no parental care and the raising of the young remains a mystery. It’s likely they go through a planktonic phase like most reef fish.
