Peacock eel – Care, Feeding, Tank Mates & Full Details!

The Peacock eel (Macrognathus siamensis), colloquially known as the Siamese spiny eel, spot-finned spiny eel, or striped peacock eel, is a marvel of aquatic biodiversity that can significantly enhance your tank’s aesthetic appeal.

Originating from the somewhat static waters of Southeast Asia, particularly the Mekong, Chao Phraya, and Maeklong River Basins, these freshwater fish are revered in the fish-keeping community.

Noteworthy, despite their eel-like elongated bodies, they’re not true eels but distinct species under a different family.

Interestingly, their care needs, although often considered challenging, are quite manageable with the right knowledge and attention to detail.

This comprehensive guide is here to unveil everything you need to know about these extraordinary fish. You’ll understand their care requirements, ideal tank mates, diet, size, and lifespan by the end of this read.

Quick Stats About Peacock Eel

Scientific name: Macrognathus siamensis
Common names Peacock eel, siamese spiny eel, spotfin spiny eel
Distribution: Thailand, Cambodia, Laos, and Vietnam
Size: Up to 12 inches
Life expectancy: 8–18 years
Color: Brown with eyespots and a yellow stripe
Diet: Carnivore
Temperament: Peaceful
Minimum tank size: 35 gallons
Temperature: 73–82°F (22–28°C)
pH: 6–7
Hardness: 6–25 dGH
Care level: Intermediate
Breeding: Egg layers


The peacock eel, an enigmatic resident of freshwaters, often misunderstood, yet an incredibly fascinating creature. This article sheds light on the care, ideal tank mates, feeding habits, size, and lifespan of this exotic species.

Despite their mysterious nature, peacock eels, also known as Macrognathus siamensis, captivate many aquarists with their unique appearance and interesting behaviors.

Let’s dive deeper into understanding this charismatic freshwater inhabitant, from their striking appearance to their origin and natural habitat, and even details about their growth, size, and lifespan.

Our goal? To help you provide the best care for your peacock eel.

Appearance of Peacock Eel

Despite their name, peacock eels are not actually eels. They belong to the Mastacembelidae family of freshwater fishes that showcase an elongated, eel-like body.

The name “peacock” is derived from the eye-catching spots they sport, reminiscent of the extravagant feathers of a peacock.

The body of a peacock eel is slim and slender, culminating in a pointed snout at the front. Unique to this species, they have distinct dorsal, anal, and caudal fins, unlike true eels.

Subtle separations exist between these fins, contributing to their eel-like persona.

Sporting a dorsal fin lined with sharp spines, they remind us to handle them with care. Though the spines may not be readily visible, they can cause significant harm if not approached with caution.

Color-wise, these freshwater residents typically exhibit a tan or yellowish-green body. A prominent streak of brighter yellow runs laterally from the snout to the caudal fin, beautifully offsetting the darker body color.

But what truly sets them apart are the spots towards their tail end, resembling eyes.

These spots, typically ranging between three and six in number, are a darker black surrounded by a ring of yellow or white. In the wild, these spots serve as a form of mimicry, fooling potential predators into thinking they are larger creatures.

Peacock Eel’s Natural Habitat

As we strive to provide the best care for our peacock eels, understanding their natural habitat is of paramount importance.

They are tropical freshwater fishes, indigenous to the slow-moving, near-stagnant water bodies of Southeast Asia.

They’re commonly found in river basins like the Mekong, Chao Phraya, and Maeklong, where the waters are rich in vegetation and teeming with life.

These habitats offer an environment that supports their burrowing and hiding behaviors, an important aspect to consider when setting up their tanks.

Origin and Distribution of Peacock Eel

The roots of the peacock eel trace back to the tranquil waters of Southeast Asia. Their distribution spans across a multitude of countries, including Cambodia, Indonesia, Vietnam, and Thailand.

In the world of fish-keeping, they are often recognized as an “oddball” species, stirring interest and enthusiasm among aquarists around the globe.

Despite their unique charm, peacock eels remain relatively unknown to many. However, their adaptability and manageable care requirements make them a great addition to home aquariums.

Growth, Size & Lifespan of Peacock Eel

Peacock eels can be considered a long-term investment for any aquarist, as their lifespan ranges anywhere between eight and 18 years, given optimal conditions.

It’s important to note that their life expectancy can be greatly influenced by factors such as water conditions, diet, and overall care.

As for their size, peacock eels stand out among other aquarium species. They can grow up to 12 inches in length, although in captivity, they typically max out at about nine inches.

This is why an adequately-sized tank is paramount to ensuring they reach their growth potential.

In summary, understanding the peacock eel, from its captivating appearance to its intriguing natural habitat, is the first step to successful care. Recognizing their origin and distribution can assist you in simulating a suitable environment.

Behavior and Temperament of Peacock Eel

Peacock eels are as interesting as they are beautiful. Known for their somewhat shy nature, they often hide during the day and become more active during dusk and dawn.

These nocturnal creatures are burrowers, preferring to burrow in soft substrates and only showing their heads.

They’re peaceful fish, not showing any significant signs of aggression towards other tank mates. This calm temperament, combined with their intriguing habits and beautiful markings, makes them a charming addition to many aquariums.

However, smaller fish might become a meal if they fit into the eel’s mouth, indicating a semi-aggressive side to them.

Peacock Eel Tank Setup: Everything You Need to Know

To mirror their natural habitat and ensure your peacock eel thrives, it’s important to create the right tank environment.

This includes not just the right tank size but also the correct substrate, decorations, water parameters, filtration, and lighting.

Understanding the right diet and tank mates also plays a critical role in maintaining their health and longevity.

Tank Size

For a peacock eel, the tank should be spacious enough to allow it to grow to its full size comfortably. Given that these fish can reach up to 12 inches, the minimum tank size should be around 30 gallons. Larger tanks are always better if possible.


Peacock eels are known for their burrowing behavior. To support this, the tank’s substrate should be soft and easily diggable. Sand or fine-grained gravel is an excellent choice as it won’t harm the eel’s skin as it burrows.

Decorations and Hiding Spots

To mimic their natural environment and help your peacock eel feel secure, include several hiding spots in your tank. Driftwood, caves, and plants work well for this. Ensure that there are no sharp edges that could potentially harm your peacock eel.

Water Parameters

Peacock eels are tropical fish, so maintaining the right water temperature, which is between 72°F and 82°F, is critical. The pH should be between 6.5 and 7.5, with a water hardness of 5-15 dGH.

Filtration and Aeration

Filtration is crucial to keeping the water clean and safe for your peacock eel. Choose a filter that can handle the tank size and the bioload. Aeration can be achieved through a good filtration system or by adding an air stone.


As nocturnal creatures, peacock eels prefer subdued lighting. Too bright lighting can stress them out, causing them to hide more and become less active. Therefore, a dimly lit tank would be more suitable.

Tank Mates

Peacock eels get along well with similar-sized, peaceful fish. Avoid housing them with aggressive species or fish small enough to fit into their mouths. Good options include larger tetras, gouramis, and other peaceful bottom dwellers.


Peacock eels are carnivores, feeding on a diet of live or frozen foods, such as bloodworms, brine shrimp, or blackworms. They may occasionally accept pellets, but this is usually not their preferred food. They are most active during feeding time, which offers an excellent opportunity for observing them.

Creating the ideal environment for your peacock eel takes a bit of planning and attention to detail.

By closely mimicking their natural habitat and understanding their unique needs, you’ll be able to provide a home where your eel can thrive and exhibit its fascinating behavior.

Tank Maintenance for Peacock Eels

The cornerstone of a thriving aquarium is regular maintenance. When it comes to caring for a peacock eel, ensuring a clean, stable environment goes a long way in keeping your fish happy and healthy.

Here’s a guide on key maintenance practices.

Regular Water Changes

Water changes are crucial in an aquarium. Regularly replacing a portion of the tank water helps keep harmful toxins at bay and provides your peacock eel with a cleaner habitat.

As a rule of thumb, aim to replace 25% of the tank’s water every two weeks. Remember to treat the new water with a dechlorinator before adding it to the tank to remove harmful chemicals.

Cleaning the Tank and Decorations

Over time, algae and leftover food can accumulate in your tank, potentially causing poor water quality and health problems for your peacock eel. Clean the tank walls and decorations using an aquarium-safe scrubber or brush.

Avoid using any cleaning agents as they can be harmful to fish. Also, remember to gently clean the substrate using a gravel vacuum to remove any waste that may have sunk to the bottom.

Filter Maintenance

A good filter not only removes debris but also helps maintain the tank’s chemical balance. However, over time, the filter media can become clogged, reducing its effectiveness.

To maintain optimal filtration, clean the filter media once a month using the tank’s water. Avoid using tap water, as it can kill beneficial bacteria that aid in breaking down waste.

Monitor Fish Health

Regularly observing your peacock eel is vital in early disease detection. Look out for signs of poor health such as lack of appetite, unusual behavior, or physical changes. If your eel appears to be unwell, contact a vet or fish health expert promptly.

Maintaining a clean and stable tank environment will help ensure your peacock eel’s health and longevity.

With regular water changes, diligent cleaning, filter maintenance, and monitoring your eel’s health, you can provide a suitable home for your underwater friend.

These steps, while simple, go a long way in enhancing the well-being of your peacock eel and making your fishkeeping experience rewarding.

Acclimating Your Peacock Eel

Introducing a peacock eel to a new aquarium environment requires patience and care. Sudden changes in water temperature, pH, or salinity can stress your new pet.

To prevent this, use the ‘drip acclimation’ method. Here’s how:

  1. Start by placing the bag your peacock eel came in, into your aquarium for about 15 minutes. This step lets the water in the bag match the temperature of your aquarium.

  2. Then, set up a siphon from your aquarium to the bag, using air tubing.

  3. Tie knots in the tubing to control the water drip into the bag.

  4. Aim for about 2-4 drips per second, which gradually introduces your eel to the aquarium water parameters.

  5. Once the bag is full, remove half the water and continue the dripping process.

  6. After a couple of hours, gently net the eel out of the bag and introduce it into the aquarium.

Peacock Eel Diet and Feeding

Peacock eels are nocturnal, carnivorous creatures with a hearty appetite. Providing a balanced, varied diet ensures your eel stays healthy and vibrant.

Here’s what to include:

Live and Frozen Food

Peacock eels love live foods like bloodworms, brine shrimp, and earthworms. These foods simulate their natural diet, promoting healthy behavior.

Frozen varieties of these foods also work well, but remember to thaw them before feeding.

Pellets and Flakes

While live foods should make up a significant portion of their diet, quality pellets and flakes add nutritional variety.

Sinking varieties are best as peacock eels tend to stay at the bottom of the tank.

Feeding Schedule

Since they are nocturnal, it’s best to feed peacock eels after the lights go out. Feed your peacock eel once a day, offering only what they can eat in a few minutes.

Occasional Treats

Occasionally, you can offer treats like small pieces of fish or shrimp to add variety and enrichment to your eel’s diet.

Remember, overfeeding can lead to obesity and tank pollution. Watch your eel’s eating habits closely and adjust portions as necessary.

A well-fed peacock eel is active, has bright eyes, and shows a willingness to explore its environment. Providing a balanced diet is a simple yet effective way to ensure your eel’s longevity and well-being.

Peacock Eel Tank Mates

When selecting tank mates for your peacock eel, consider their peaceful nature and nocturnal habits. They prefer companions who are not too small (to avoid becoming a meal) and not too aggressive (to avoid stress).

Here are some ideal companions:

Gouramis: Known for their calm demeanor, gouramis can coexist peacefully with peacock eels.

Corydoras Catfish: These bottom dwellers are non-aggressive, making them great tank mates.

Large Tetras: Fish like Congo tetras can share the tank without fear of being eaten.

Angelfish: With their similar size and calm nature, angelfish can make good companions.

Rainbowfish: These active swimmers will stay out of your eel’s way.

Bichirs: Their similar habitat preferences and peaceful temperament make them suitable tank mates.

Tank Mates to Avoid

Just as important as knowing who to invite into your peacock eel’s environment is knowing who to leave out.

Here are some species to avoid:

  1. Small, Invertebrates: Shrimp and small snails can easily become a tasty meal for your eel.

  2. Small Fish: Neon tetras, guppies, or any fish small enough to fit in the eel’s mouth should be avoided.

  3. Aggressive Fish: Species like cichlids or tiger barbs can stress your eel with their aggressive behavior.

  4. Bottom-Dwelling Fish: Too many bottom dwellers like loaches can crowd your eel and lead to territorial disputes.

  5. Larger Predatory Fish: Fish larger and more aggressive than your eel can pose a threat.

Peacock Eel Breeding and Fry Care

Breeding peacock eels in home aquariums is a challenge due to their secretive nature and specific breeding conditions.

It’s rarely achieved but here’s what is understood:

Breeding Conditions

Create a conducive environment by keeping the water clean, maintaining the right temperature (78-82°F), and offering plenty of hiding spots. Provide a diet rich in live food to trigger spawning.

Mating Behaviour

When ready to breed, males will perform a dance-like display around the female, involving side-to-side movements and flaring fins.

Egg Laying

Once the female accepts the male’s advances, she will lay hundreds of eggs within hiding spots. Both parents guard the eggs, showing a rare level of parental care in fish.

Fry Care

After hatching, the fry can be fed infusoria or newly hatched brine shrimp. Once they are large enough, they can be introduced to larger food like daphnia.

Remember, peacock eels are very secretive during breeding, and it’s easy to miss the signs. Regular observation and consistent tank management can improve the chances of success.

Stress Signs in Peacock Eels

Peacock eels, like all fish, can exhibit signs of stress when their environment isn’t quite right.

Here are some indicators to watch out for:

  1. Loss of Appetite: If your eel starts to eat less or refuses food, this can indicate stress or illness.

  2. Erratic Swimming: Unusual or frantic movements can be signs of stress.

  3. Constant Hiding: While peacock eels are nocturnal and love to hide, excessive hiding may suggest that they’re not comfortable in their environment.

  4. Loss of Color: A stressed eel may lose some of its vibrant colors.

Common Peacock Eel Issues

Peacock eels can face health issues like any other fish.

Here’s what to look out for:

  1. Ich: Also known as white spot disease, Ich can be treated by raising the tank’s temperature slowly to 86°F and using over-the-counter Ich treatments.

  2. Skin and Gill Flukes: These parasites cause irritation, and can be treated with anti-parasite medication.

  3. Bacterial Infections: These often occur due to poor water quality. Regular tank maintenance and water changes can help prevent these issues.

Aquarium Success: Additional Tips

Creating a healthy aquarium environment doesn’t stop with setup.

Here are some additional tips:

  • Regularly check water parameters and adjust as necessary.

  • Add new fish slowly to avoid overwhelming your established aquarium community.

  • Don’t overfeed your fish. Feed them in small quantities they can consume in a few minutes.

Is a Peacock Eel Right for Your Aquarium?

Considering a peacock eel for your tank? They can make a fascinating addition to any aquarium, given their unique appearance and interesting behavior. However, they do require special care.

If you’re up for the challenge of providing the right environment and don’t mind their nocturnal nature, a peacock eel could be the perfect new member of your underwater family.

They might not be the right choice for a beginner, but for an aquarist with some experience, they can be a very rewarding pet.

Conservation Status of Peacock Eels

As of now, the conservation status of Peacock eels is not critically endangered. The International Union for Conservation of Nature (IUCN) has not classified this species, suggesting they are currently not at immediate risk.

However, maintaining sustainable fishing practices and responsible pet trade is critical to the long-term wellbeing of this species.

Availability and Pricing of Peacock Eels

Peacock eels are commonly available in pet stores and online aquarium fish shops. The pricing of these eels can vary depending on the size and age of the fish.

Generally, you can expect to pay between $10 to $20 for a Peacock eel. However, prices can differ based on availability, location, and the store’s pricing strategies.

Frequently Asked Questions About Peacock Eel

1. Do Peacock Eels need a tank mate?

While Peacock eels can live alone, they often appreciate the company of other peaceful and similarly sized fish. Always ensure the tank mates are compatible to avoid stress and territorial issues.

2. How big does a Peacock Eel get?

Peacock eels typically grow to about 12 inches in captivity. Their growth may be impacted by factors like diet, tank size, and overall health.

3. Can Peacock Eels live in a community tank?

Yes, as long as their tank mates are peaceful and non-aggressive. Additionally, the tank should be large enough to accommodate the eel and its companions comfortably.

4. What do Peacock Eels eat?

Peacock eels are carnivorous and prefer live or frozen foods like bloodworms, brine shrimp, and small pieces of fish or meat.


Peacock eels are fascinating creatures, boasting unique patterns and behaviors. They can be a fantastic addition to your aquarium, provided they’re given the right care and environment.

Their captivating nature, coupled with their distinctive look, make them a joy to watch and care for.

They may not be the easiest fish to care for, but for aquarists willing to meet their specific needs, the reward is a vibrant and intriguing underwater friend.