Black Kuhli resting

Black Kuhli Loach – Perfect for Your Aquarium?

While the common Kuhli loach is a favourite in tanks around the world thanks to it’s cute striped brown or black appearance and even more adorable shy nature.

Little known though is the Black Kuhli Loach, which although dark in appearance, shimmers like a rainbow under the light, more resembling the natural colours of fish often seen in freshwater lakes.

The first time I stumbled upon one of these fascinating creatures over 15 years ago, I was mesmerized by their foraging snuffle-pig eating style and beautiful elegance.

If you love Kuhli Loaches? Check out the Dinosaur Bichir!

Originally, hailing from the slow-moving rivers and streams of Southeast Asia, the black kuhli loach is stocked in aquariums worldwide, although you might find it hard getting your hands on one.

In this Black Kuhli Loach Mini Guide, we’ll give you a snapshot of everything you need to know before adding one of these little loaches to your aquarium setup.

Black Kuhli Loach hiding after being introduced to new fish tank

NameBlack Kuhli Loach
Scientific NamePangio oblonga
Max Size8cm (3.2″)
Lifespan8-12 years
AppearanceEel with dark body & Rainbow Shimmer
Water ParametersSoft and slightly acidic; pH: 5.0-7.0; dH: up to 12 degrees
Compatibility with Other FishCommunity
Community SizeGroup of 3 or more
BehaviorPeaceful and social
LightingDim/Hiding Spaces
FeedingCatfish pellets, flake and frozen foods
Breeding DifficultyChallenging (Breeding Guide

Black Kuhli Loach: Snapshot

Related: Hillstream Loach Care Guide

Related: Yoyo Loach: Cleanup Crew Legend!


The black Kuhli loach is as captivating in appearance as in personality. With their dark, almost black colouration, shiny rainbow effect highlights and elongated, eel-like body, they’re real eye-catchers. (Although a little too snake-like for some).


Typically, the Black Kuhli loach grows to a length of around 3 to 4 inches. This manageable size makes it suitable for all but nano-aquariums.


Don’t let their shy nature fool you; the Black Kuhli loach is an adventurous eater. Omnivorous by nature, they relish both plant matter and small aquatic creatures. From nibbling on soft algae to feasting on brine shrimp, their varied diet keeps them happy and healthy.

Their foraging/digging nature makes them valuable tank cleaners, rooting out hidden food particles that other fish might overlook.

Do Black Kuhli Loach eat Snails?

Just like regular Kuhli Loaches, the Black Kuhli Loach doesn’t actively hunt for snails but will eat snail eggs and small snails if it finds them while foraging around your tank.

If you’re looking for the best snail control fish to add to your aquarium, here’s a list of Fish that love to eat snails!

Black Kuhli Loach swimming


Gentle and peaceful, the black Kuhli loach (wiki) is an ideal community fish. They prefer the company of their kind, often seen playfully twisting around one another.

Yet, they are equally content with other non-aggressive tank mates. Though they may appear shy at first, hiding under rocks or within plants, give them time and a stable environment, and you’ll witness their social and curious side emerge.

Where the heck have my Black Kuhli Loaches gone?

As any seasoned keeper of Kuhli Loaches knows, these shy little guys can switch to a fully nocturnal lifestyle, burying themselves in the substrate throughout the day.

In a well-stocked community tank, I hadn’t seen my Kuhli loaches for weeks. Eventually, after changing out some aquascape and re-mossing some rocks, I found all three of the shy little fat, happy and healthy.

Psychic Loaches?

Some even say that the black kuhli loach can tell when a storm is incoming…

I’ve kept Kuhli loach for many years and they certainly act strange when there’s a lightning storm incoming. Coincidence? Maybe…

Black Kuhli Loach resting on lead

Aquarium Care for Black Kuhli Loach

Substrate and Plants: Creating a Comfortable Environment

Black kuhli loaches love to burrow, so a soft, sandy, or small substrate is ideal. Also adding lush plantations to mimic their natural habitat, helps make them feel safe around other fish.

Don’t know what plants to add to your tank? Check out our quick guides below:

Expert’s Tip: Choose fine sand rather than gravel to prevent injuries to their delicate bodies. Live aquatic plants create hiding spots, enhancing their comfort.

Water Conditions: Maintaining Optimal pH and Temperature

For black kuhli loaches, keep the pH between 5.5 and 6.5, and the temperature between 75-85°F (24-29°C).

Dark Black Kuhli Loach

Diet in the Tank: Feeding Guidelines

A varied diet is key. Offer a mix of pellets, frozen, and live foods like bloodworms and brine shrimp.


Kuhli loaches in general prefer dim lighting in their aquarium environment. Bright lights can cause stress for them, so subdued or shaded lighting is often recommended.

This doesn’t mean you have to have a dim aquarium though. Since Black Kuhli Loaches often hide/sleep throughout parts of the day, you can set up your lights to dim in the evening and encourage your loaches to come out from hiding.

Floating plants and other forms of cover can be used to help diffuse the lighting and create the darker, more natural environment that they prefer.

Adding a cave or dark tunnel will also put a big smile on your new little friends’ eely faces. Somewhere they can curl up on each other and rest.

Black Kuhli Loach next to regular Kuhli Loach

The Black Kuhli Loach: Considerations

The biggest concern you need to think about before adding Black Kuhli Loaches to your aquarium is stocking. These cute little eels love to live in groups of 3+ to be happy and stress-free.

Adding 3 or more 3-4″ long fish in your tank is going to add a lot of bio-load so make sure your tank is big enough and you’ve calculated your stock properly.

For most small tanks, 3-5 new Black Kuhli loaches are going to be too much. While small and cute in your local fish shop, they grow up fast.

It’s also worth considering that Kuhli Loaches can be very shy and turn nocturnal if they don’t get along well with the other fish in your aquarium.

With these concerns out of the way, they are truly full of characters and great substrate cleaners for your aquarium.

If the darker rainbow colouration of the Kuhli Loach isn’t for you, check out the common Kuhli Loach here, with its bright orange and brown stripes! Super Cute!

Have more questions or need personalized advice? Feel free to reach out to me directly, and I’ll be glad to assist you with any of your black kuhli loach questions.

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