Peacock Eel Care Guide: Tank Size, Diet & Tankmates
The peacock eel is one of the most rewarding oddball fish you can keep, and a tank-bred favorite for hobbyists who want something a little different from the usual community lineup. Despite the name, it is not a true eel at all but a spiny eel in the genus Macrognathus. At Tropical Treasures we usually stock the Indian Peacock Eel (Macrognathus siamensis), the classic peacock-spotted spiny eel, and often its close cousin the Banded Spiny Eel (Macrognathus circumcinctus). Availability changes as fish come and go, so it is always worth a quick message or a stop in the store to see what we have swimming right now.
Meet the peacock eel
Peacock eels are slender, snake-like bottom dwellers named for the row of peacock-like "eye" spots along the back near the tail. They reach roughly 8–12 inches in the aquarium, with the Indian peacock eel usually staying on the smaller end. They are shy, nocturnal, and famous for burrowing into soft substrate with only their pointed snout poking out. Give one a few weeks to settle and you will be rewarded with a curious, almost puppy-like fish that learns feeding time and comes out to hunt. You can browse more unusual fish like this in our oddballs collection.
Tank Size and Setup
A single peacock eel needs a tank of at least 29–40 gallons with plenty of floor space, since these fish spend their lives along the bottom rather than the water column. The two most important pieces of the setup are a soft, fine substrate and a tightly fitting lid. A sand bottom such as CaribSea Jungle River Sand lets the eel burrow naturally and protects its delicate skin—sharp gravel can cause scrapes and infections, so always choose sand from our substrate collection. Add caves, driftwood, and dense planting so your eel has dark hideaways to feel secure during the day.
One warning every keeper should hear: peacock eels are escape artists. They will find any open corner or filter gap, so a tight lid with no gaps is non-negotiable.
Water Parameters and Heating
Peacock eels are tropical fish that do best at 73–82°F, a pH of about 6.5–7.5, and soft to moderately hard water. They are sensitive to poor water quality and dissolved waste, so a well-cycled tank, gentle filtration, and regular water changes matter more than for many hardy community fish. Keep an eye on ammonia and nitrite, which should always read zero, and aim to keep nitrate low. Like most scaleless and fine-scaled fish, they can be touchy about medications, so dose conservatively if you ever need to treat the tank.
Feeding Your Peacock Eel
This is where new keepers most often go wrong: peacock eels are carnivores that strongly prefer meaty foods, and many individuals refuse dry flakes entirely. Build the diet around frozen and live foods such as frozen bloodworms, tubifex worms, and live brine shrimp. You can explore more options in our frozen fish food collection. Feed in the evening when the eel is naturally active, and over time many will accept sinking pellets too. Because they hunt by scent in the dark, target feeding near their burrow helps make sure they get their share.
Tankmates and Temperament
Peacock eels are peaceful toward fish too big to eat but will happily swallow anything small enough to fit in their mouth, so skip tiny tetras, shrimp, and fry. Good companions are calm, medium-sized community fish and other peaceful bottom dwellers that occupy different zones of the tank. Larger catfish and bottom dwellers, loaches, and an algae eater like the rubber lip pleco all work well. A gentle centerpiece such as the keyhole cichlid can round out the tank. If you enjoy oddballs, the Senegal bichir shares a similar nocturnal, carnivorous lifestyle, though it needs more space.
Is the Peacock Eel Right for You?
A peacock eel is a great pick if you want a hardy-once-settled, personality-packed oddball and you are willing to feed meaty foods, provide sand, and keep a tight lid. It is not the best choice for a tank full of tiny fish or for keepers who only want to feed flakes. If you are still building experience, you might start with a hardier community setup—our guide to the kribensis cichlid is a friendly place to begin, and you can read our take on buying fish in store versus online before bringing an eel home.
Frequently Asked Questions
Do peacock eels need a lot of light? No—they are nocturnal and prefer dim, shaded tanks with plenty of cover. Low light and floating plants help them feel secure and come out more often.
Will a peacock eel hurt my other fish? Only fish small enough to be eaten. Toward similarly sized or larger tankmates they are gentle and shy, spending most of the day hidden.
Why won't my peacock eel eat? New eels often refuse food for days or weeks while they adjust. Offer frozen bloodworms or live foods after lights-out near their hiding spot, keep the water clean, and be patient—most come around once they feel safe.