Purple Spaghetti Eel

The intriguing Purple Spaghetti-eel is extremely rare, so deserves the best attention we can give it!

The Purple Spaghetti Eel Moringua raitaborua is not only rare in the aquarium trade, but this curiosity is also rarely viewed once it’s added to the aquarium. It is very shy so it will keep itself hidden and spend most of its time burrowed in a fine sand substrate.

This is a ‘true’ eel. It is a member of the Moringuidae family of ‘worm eels’ or ‘ spaghetti eels’. It can get rather long, growing to just over 17 inches (44 cm) in length. But true to its name its body is long, thin, and ‘spaghetti’-like. Its head is so small that it is inconspicuous from the rest of the body. It eyes are small too and are covered with skin.

It is called the Purple Spaghetti Eel not only because of its spaghetti-like body, but also due to its rather pinkish or purplish brown color overall. It is also called the Pink Paddletail Eel. This name refers to the color but also its fins. The dorsal and anal fins are towards its back end, but are more like folds. They are joined with the caudal fin giving it a paddle type extension on the back end.

All the members of the Moringuidae family are carnivores and the majority of the species are saltwater fish. This eel is a carnivore too but due to its small head and mouth, it is no threat to most tank mates in a community aquarium. Also rather than being a saltwater fish, the Purple Spaghetti-eel primarily Inhabits estuaries (the tidal mouths of rivers flowing into the ocean). It will do well in a slightly brackish aquarium and probably in a freshwater environment as well.

Despite the length and body shape, Purple Spaghetti-eels are thought of as a small fish. Yet it is advisable to keep them in a tank that is at least 30 gallons with a fine sand substrate for them to bury themselves in. When you do have a chance to glimpse it, it will be a source of pleasure and wonder. This is a species that is truly worth keeping if you are an exotic aquarist with a love of the unusual. Frank Schaefer, an avid aquarium enthusiast from Germany, reports only five face to face viewings of this eel in two years of keeping it.

For Information on keeping freshwater fish, see:
Freshwater Aquarium Guide: Aquarium Setup and Care

Habitat: Distribution / Background

The Purple Spaghetti Eel Moringua raitaborua was described by Hamilton in 1822. They are found in the Eastern Indian Ocean: Gangetic estuary (West Bengal) in India, Matla and Bidyadhari river, and probably Bangladesh; Indonesia and the Philippines. This species is not listed on the IUCN Red List. Other names it is known by are Pink Paddletail Eel, Purple Spaghetti-eel, Spaghetti Eel, and Paddle-Tailed Eel.

They are found in freshwater, brackish water, and saltwater environments. These eels can be found in freshwater when young and then may move to more brackish water, or even into the ocean as they mature. They generally inhabit the underflow areas of rivers and estuaries where the substrate is soft. In nature these eels feed on crustaceans, insects, larvae and small fish.

• Scientific Name: Moringua raitaborua
• Social Grouping: Groups
• IUCN Red List: NE – Not Evaluated or not listed

Description

The Purple Spaghetti-eel is a ‘true’ eel, a member of the Moringuidae family of ‘worms and spaghetti eels’. True to its name its body is long, thin, and ‘spaghetti’-like. This eel can grow up to about 17 1/3 inches (44 cm) in length and generally has a life span of 5-12 years. The body is a pinkish gold to a light purplish-brown color.

The head of this spaghetti eel is very small and inconspicuous from the rest of the body. Its eyes are also very small and covered with skin. Their gill openings are set low on the body. The body is covered with smooth skin and they have no scales. The dorsal and anal fins are more like folds towards the back end of the eel and are joined with the caudal fin.

• Size of fish – inches: 17.3 inches (43.99 cm) – This eel can reach up to about 17 1/3 inches (44 cm) in length.
• Lifespan: 12 years – These eels have a lifespan of 5 – 12 years.

Fish Keeping Difficulty

This eel is suggested for the more advanced aquarist. It can be a bit sensitive to change and usually takes awhile to get over its shyness. The first few weeks it can be difficult getting them to eat. They require extremely pristine water and are primarily a brackish water species. They are also scaleless so are prone to fungus and parasites and very sensitive to medications. These fish respond poorly to copper based medications, so these should be avoided. For long tern success with this eel brackish water experience is best.

• Aquarium Hardiness: Difficult
• Aquarist Experience Level: Advanced

Foods and Feeding

The Purple Spaghetti-eels are carnivores. In nature they feed on very small prey, primarily insect larvae but also on crustaceans and small fish. They are likened to an “insect larvae eating version of a moray eel “. In the aquarium this fish likes to eat tubifex and bloodworms as well as brineshrimp, preferably live although frozen food will probably also be accepted.

Their mouths are very small, but being carnivorous they may also eat small fishes like livebearer fry, neons or guppies if given the chance. This fish likes to feed at night, but can be fed in the daytime as well in the rare instance when they are out of hiding.

• Diet Type: Carnivore
• Flake Food: No
• Tablet / Pellet: No
• Live foods (fishes, shrimps, worms): Some of Diet
• Meaty Food: All of Diet
• Feeding Frequency: Daily – This fish likes to feed at night.

Aquarium Care

The most important thing for these eels is that they always have clean and well-oxygenated water. Frequent water changes of about 30% a week are needed. With your weekly water change make sure to vacuum the gravel to remove all excess food and waste, but it’s best not to remove any bio film on the rocks and decor. A magnet algae cleaner normally does a great job in keeping the viewing pane clear.

It is also helps to add efficient bottom cleaning tank mates to keep the bottom free from decaying foods in between cleanings. Be careful however, to add bottom cleaners after your eel is adjusted to its tank and is eating.

• Water Changes: Weekly – Water changes of about 30% weekly.

Aquarium Setup

Purple Spaghetti Eels with spend most of their time burrowed in the substrate at the bottom of the aquarium. Although this fish is thin and ‘worm-like’ it can grow to be just over 17 inches long. Due to their length It is advisable to keep them in a tank that is at least 30 gallons. They do best in a soft, slightly acidic water with good water movement that provides plenty of oxygenation. The tank water should turnover at least 10-15 times per hour. An undergravel filter is a great choice for these fish as it creates high oxygen through out the tank as well as reducing the waste. A canister filter or powerheads and airstones can be introduced to achieve proper flow and oxygenation.

They require extremely pristine water and are primarily a brackish water species. You may be able to keep this spaghetti eel in freshwater for short periods, but a mid-level brackish environment is preferable. For long term health the specific gravity should be kept at 1.005 – 1.010. This can be created by adding 2 – 3 teaspoons of salt for each 2 1/2 gallons of water. An entry for this species in Schaefer’s Aqualog book also suggests that brackish water helps prevent fungus, though that may not be significant with this eel. Eels respond poorly to copper based medications, so these should be avoided.

As they are very shy and like to burrow, the tank should have a fine sand substrate for them to bury themselves in. Plenty of hiding places provided with rocks, roots, and plants may also help them feel secure in their new home. These eels can fit through very small openings, so be sure to have a tight fitting lid. Also to prevent any injuries, make sure the intakes to pumps and powerheads are covered with either netting or sponge material.

The water parameters suggested below are based on recommendations for this eel’s saltwater relative the Spaghetti Eel Moringa microchir. They are approximations of wild conditions, as precise tolerance ranges have yet to be established.

• Minimum Tank Size: 30 gal (114 L)
• Suitable for Nano Tank: No
• Substrate Type: Sand – These eels like to burrow and have delicate skin, so make sure the substrate is smooth and soft.
• Lighting Needs: Low – subdued lighting – In moderately lit tanks, provide floating plants to help subdue the light.
• Temperature: 72.0 to 78.0° F (22.2 to 25.6&deg C)
• Range ph: 8.1-8.4
• Hardness Range: 8 – 12 dGH
• Brackish: Yes – As adults they will do best with a specific gravity of 1.005 – 1.010.
• Water Movement: Moderate
• Water Region: Bottom – Purple Spaghetti-eels with spend most of their time burrowed in the substrate at the bottom of the aquarium.

Social Behaviors

This eel is extremely shy and will spend most of its time buried head first in the soft substrate. Due to its small head and mouth, it is no threat to most tankmates in a community aquarium. However it is a predator of benthic invertebrates (insect larvae, worms, etc.) as well as small fish. In a community tank it could snack on fish small enough to fit in its mouth. Make sure their tank mates are too large to eat. You may want to avoid small species such as like livebearer fry, neons, and guppies. Also do not house them with larger more aggressive eels.

• Venomous: No
• Temperament: Peaceful
• Compatible with:
  • Same species – conspecifics: Yes – They can be kept together if the tank has enough room for each eel to have undisturbed territories. Then try to keep like sized fish together.
  • Peaceful fish (): Safe – Very small fish that will fit in its mouth will be eaten.
  • Semi-Aggressive (): Monitor – More aggressive fish may nip at the eel.
  • Aggressive (): Threat
  • Large Semi-Aggressive (): Monitor
  • Large Aggressive, Predatory (): Threat
  • Safe
  • Shrimps, Crabs, Snails: May be aggressive
  • Plants: Monitor – Make sure roots are anchored. These eels like to burrow and mayuproot most plants.

Sex: Sexual differences

Mature females are normally more deeper-bodied than the males.

Breeding / Reproduction

The Purple Spaghetti Eel has not been bred in captivity.

• Ease of Breeding: Unknown

Fish Diseases

Purple Spaghetti Eels are scaleless and prone to diseases caused by parasites and fungus, so take caution when introducing these fish to an established tank. Very low water temperatures and condition changes can also cause stress to this fish which makes them even more prone to disease. They are also very sensitive to medications used to treat many diseases; a separate hospital tank is needed. These fish respond poorly to copper based medications, so these should be avoided. Take great care when netting eels as they have very delicate and scraps can make them even more prone to disease.

Most common disease that eel are susceptible to is Ich. Ich is short for Ichthyophthirius, also known as “white spot disease”. It is a parasite that can attack nearly all aquarium fishes, but you’ll find that Eels are often the first to be attacked. Take great care in treating ick as eels are very sensitive to the medications used to treat it. Often the dose is half of what is normally used. If nervous or unsure about medications, use Reef safe medications.

An outbreak of disease can often be limited to just one or a few fishes if you deal with it at an early stage. When keeping these sensitive types of fish, it is common to catch deteriorating water conditions and disease before other fish are affected. The best way to proactively prevent disease is to give your Spaghetti Eel the proper environment and give them a well balanced diet. The closer to their natural habitat the less stress the fish will have, making them healthier and happy. A stressed fish will is more likely to acquire disease.

Anything you add to your tank can bring disease to your tank. Not only other fish but plants, substrate, and decorations can harbor bacteria. Take great care and make sure to properly clean or quarantine anything that you add to an established tank so not to upset the balance. It is recommended to read up on the common tank diseases. Knowing the signs and catching and treating them early makes a huge difference. For information about freshwater fish diseases and illnesses, see Aquarium Fish Diseases and Treatments.

Availability

Purple Spaghetti-eels are pretty scarce and are available only on rare occasions.

References

• Animal-World References: Freshwater Fish and Plants
• Joseph S. Nelson, Fishes of the World, Wiley, 2006.
• Frank Schaefer, Purple Spaghetti-eel pictures and notation, Germany, aqualog.de, referenced online, 2007
• Neale Monks, Brackish Water Fishes: An Aquarist’s Guide to Identification, Care & Husbandry, TFH Publications, 2006
• Moringua raitaborua (Hamilton, 1822) Purple spaghetti-eel, Fishbase.org