Kuhli Loach – A Comple Species Profile, Care and Guide

Kuhli Loach
Kuhli Loach is also known as Coolie Loach, is a slender snake looking nocturnal fish.
Kuhli Loach is a scavenger fish that dwell at the bottom cleaning. They enjoy burrowing in the soft substrate and stay awake all night long, scavenging your tank.
This eel looking fish is shy with a peaceful temperament. Despite its shy nature, they are friendly and comfortable in the companionship of the other loaches.
To know whether it is suitable for you or not and how to care for this creepy looking fish with strange habits, let’s continue reading.
Kuhli Loach – an Overview
Description Category
Family Cobitidae
Scientific name Pangio kuhlii
Origin Southeast Asia
Type Fresh Water
Color Form yellow and brown
Difficulty Intermediate
Max. Size 5 inches (13 cms)
Life span 10 years
Temperament Peaceful
Diet Omnivores
Minimum Tank Size 20 gallon (75 liters)
Temperature 75°-86°F (24°-30°C)
Acidity 5.5 to 6.5 pH
Hardness 5 dGH

Species Origin:

Kuhli loach, coolie loach, khuli loach, cinnamon loach, the prickly eye that originates from Southeast Asia, the streams of Indonesia, Singapore, Malaysia, Java, Borneo, Sumatra, and Thailand. 

Earlier it was known as Acanthophthalmus. They are one of the 33 recognized species of Pangio. They all are widespread across Southeast Asia but of the 5 of the species. The five of these species are from India and Myanmar.

Most of the species resemble each other. Quite often one might end up buying the wrong loaches. Kuhli loach or coolie loach are frequently confused with Pangio cuneovirgataPangio myersi, Pangio sumatuanus and Pangio semicincta.

They are prone to some specific diseases and parasites, and they are sensitive to medications. Therefore, Khuli loach needs some experienced hands to care for them.


In nature, Kuhli loach lives from 10 to 14 years. In your tank, their life span depends upon how well they are cared for by you. It comes down to their diet, water parameters, and not discount their tankmates.

Poor water quality increases their chance of contracting diseases, and an easy target for parasites. Wrong tank mates might keep their adrenalin up, and keep them under the burrows that eventually shortens their lifespan.

Physical Characteristics of Kuhli Loach:

Coolie loach can be easily mistaken for an eel due to their physical features. They are slender and have rather small fins that are rarely visible.

Most Khuli loaches base color ranges from Salmon pink to brassy yellow. The underside of the fish is lighter. They have 10 to 15 dark brown to black verticle stripes. These dark brown stripes may partially or fully encircle their body just like in tigers. They don’t have any lateral lines.

Their dorsal fins start beyond the middle of the body and beyond that anal fins are located. They have 4 pairs of whiskerlike sensory organs around their mouth.

The eyes are covered by transparent skin. They have a pair of sharp bristles underneath their eyes. These bristles snap out when they are defensive. This feature gave them the name Acanthopthalmus, meaning “prickle-eye.”

They have very faint body scales, which makes them vulnerable and susceptible to diseases and parasites attack.

All the scaleless fish are sensitive to salt and medications. 

The distinction between the male and the female of the species is not perceptible when they are not breeding. Nevertheless, close inspection will reveal that the male of the species has sturdy dorsal with larger pectoral fins. Most time have some pigmentation in them.

When breeding the females tend to be larger than their male counterparts, and the ovaries will be visible through their skin before spawning.

How Big Are Kuhli Loaches?

In their natural habitat, they grow as long as 5 inches (13 cms). No species in captivity can grow to their maximum potential size. In your tank, they will grow anywhere between 3 to 4 inches (8 to 10 cms).

Black Kuhli Loach:

Black Kuhli Loach

Black Kuhli Loach is a popular variant of Kuhli loach.  Its Scientific name Canthophthalmus javanicus. This black variant is completely black and smaller than the other Kuhli Loach. 

They are alluring to the aquarists as their look is different from other Kuhli loaches with stripes. They are known as Chocolate Kuhli Loaches among the aquarists. Their behavior is just the same as the other normal Coolie Loach.

They reach a maximum length of 3.5 inches (8 cms).

Kuhli Loach Food and Diet:

Kuhli Loach is bottom-dweller scavenger fish. They are natural omnivores that can eat just about anything. They are nocturnal that creep around at night and clean up all the leftovers in the night.

Although they feed on the leftovers, you can feed them some specific food, such as sinking food like pellets, flakes, and algae, that sink to the bottom of the tank.

You can also feed them with frozen bloodworms, live blackworms, daphnia, tubifex, artemia, grindal worms, water fleas, brine shrimps, and some home-prepared food.

Make sure to feed them a balanced diet, frozen as well as live food. The best time to feed your Coolie loaches is at night after you switched off the lights.

Kuhli Loach habitat:

Kuhli Loaches originate from Southeast Asia, the streams of Indonesia, Singapore, Malaysia, Java, Borneo, Sumatra, and Thailand. 

In nature, they inhabit slow-moving shallow waterways. Their environment is similar to one of forest peat swamp, where the soil saturated with water preventing dead leaves and wood from fully decomposing.

The water where they live is almost black. Generally, the vegetation with canopies around these streams blocks the Sunlight. The waters tend to be on the acidic side with a temperature ranging from 75° to 86°F (24°-30°C).

The substrates of these waterways are soft to yield to their burrowing nature.

Keep their natural habitat in mind while creating their new home.

Behavior and temperament:

Kuhli Loach is a peaceful fish. They are nocturnal by nature. They can be very shy when left alone. Despite being non-schooling fish, they are comfortable in the companionship of their kind. 

You may not see them at all during the day despite the companionship. They will remain quiet in their hideouts. As soon as the lights are off, you will see them poking their head out slowly and become active scavenging. 

As in their natural habitat, they will be digging the substrate for their food. Even at night, you will not see them swimming in the middle or coming to the surface of the tank. They are bottom dwellers. 

They are curious would like to explore every nuke and corner of the tank. 

In general, they are peaceful and mind their business. However, when threatened, the sharp spikes situated under their eyes shall pop to defend themselves.

Tank size:

They require a minimum tank size of 20 gallons (75 liters). Coolie Loach is a shy fish, hence, given each one of them enough space to come out of their burrows and explore the bottom of your tank. This way, they can do the job for which they are there, which is sweeping and mopping your tank floor. Aquarist recommends you to allow each Kuhli 3 to 5 gallons (12 to 20 liters).

Tank Setup and Water conditions:

Consider their natural habitat, their behavior, and their temperament while preparing their tank. 

Tank and Substrate:

Kuhli Loaches need a smooth substrate that is safe to dig, such as peat, sand, and smooth gravel. Some experienced aquarists advise for rocky gravel substrate with minimum sand.
Don’t let their docile nature fool you; make sure the tank lid is tight in its place as Kuhli loaches jump out of the tank, despite them being bottom dwellers, especially when they are startled.
As we repeatedly mentioned in this article that Kuhli Loaches like to explore with their curious and burrowing nature that includes the filter inlets and outlets. Therefore, make sure to keep filtration inlets and outlets in the tank covered with a sponge pre-filter.
When we say pre-filter, we do not mean a pre-filter basket or any high-tech equipment. A perforated strainer with a well stuck sponge to prevent our cleaner friend from being sucked in.

Water Parameters:

In their natural habitat, the stream water is soft, warm, and acidic due to the constant decomposition of leaves and other organic matters.
The aquarium waters parameters should maintain the calcium level 5 dGH, the pH level between 5.5-6.5 and the temperature of the water 75°-86°F (24°-30°C).
To maintain the aquarium water clean, you need to have a filtration system with a rate of medium to high.

Plants and Decors:

As we already know, they are shy fish and like to hide in their burrows. While choosing plants and decors, consider their nature.
They need some dark hiding places, plants such as java moss, Java fern, anubias, Cryptocoryne, etc. can provide plenty of hiding places.
Well-placed rocks and driftwoods can provide excellent crevices.


Kuhli Loach is a slender, small eel-like fish that does not grow over 4 inches (10cms) in your aquarium tank, which is nocturnal by nature.
You will see them only when the lights are down. This nature makes it hard for us to see them during the day.
Add a moonlight in the tank to observe them while they come out of their burrows and perform their duties.
Kuhli Loach Tank Mates:

Kuhli Loach is a peaceful and non-aggressive fish. They are best to keep with other non-aggressive, small mates, such as neon tetra, ember tetra, rasboras, celestial pearl danio, zebra tetra, platyfish, Gouramis, etc.

Tetras being middle dwellers that dip down to the bottom level of the tank, make them an excellent tank mate for our bottom-dweller Kuhli Loach.

You can have a dazzling aquarium by choosing some colorful fishes as mates to your Kuhli Loach that will keep the aquarium nice and clean.

Kuhli Loach is a shoaling fish, thus, keep them in a group of 6 or more. Alone, they will be shy and stressed.

Kuhli Loach Tank Mates

Tanks mates to avoid:

Avoid keeping your Coolies with any kind of large, aggressive, and territorial fish like Jack Dempsey and other cichlids. Even Cichlids like angelfish that are community tank fish should not keep with Kuhli Loaches.
You should avoid Gouramis and bettas with Coolies, as they are aggressive and territorial.
Do not bring any catfishes, pacus, or gar near these peaceful Khulis.
Do not keep snails with our bottom-dweller cleaning agent will eat them.

Care for Kuhli Loach:

Khuli loach needs some experienced hands to care for them. Unfortunately, they are susceptible to diseases since they don’t have any head scales and scanty body scales.
They are very sensitive to medicine and other chemicals used in the aquarium trade. Acclimatize the tank environment suitable to Kuhli loach before adding them to the tank.
One of the most common diseases among aquarium fish is white spot disease, also known as ich. Kuhli Loaches are the first and easy targets.
The skinny disease is another common disease in the aquarium, caused by parasites. If your Khulis remain thin after eating well, then it is most likely Parasites are the cause. Promptly consult the vet.
It requires some minimum amount of experience to watch out for Kuhli Loaches.
Prevention is better than cure when you are dealing with such a sensitive fish as Kuhli Loach.
Maintain the tank water clean and well-circulated and provide them with the right environment to thrive.

Breeding Kuhli Loach:

Breeding Kuhli Loach is not an easy task. It can be challenging even for an experienced aquarist.

The first step in breeding Kuhli Loach is to get a separate 20 gallons (75 liters) tank ready with low water levels, dim light, and dense vegetation. It is paramount to have floating plants, such as java moss, water lettuce, etc. 

The water pH should be 6.5, and the temperature should be maintained around 83°F (28°C). Keep the water clean through sponge filtration.

Once the tank is ready, give the loaches time to settle and get comfortable. The key to succeeding in breeding Kuhli Loaches is providing them an environment where they are comfortable.
They become comfortable in the presence of dense vegetation, just like in their natural habitat. The more comfortable they are, the more the chances of them spawning.
5% water change daily. You may want to top it up with cold water after you turn off the light.
Note, Kuhli Loach reaches its sexual maturity only at the age of 2 years.
Plenty of food is appreciated to stimulate spawning. Feed the adult Kuhli Loaches protein-rich food, such as blood worms, brine shrimps, etc. Live foods are more appreciated.
If everything goes well, one can witness a pair of Kuhli Loach swimming together. The only time you will see the Loaches at the surface is during the mating. You will notice that the females start to get larger, sometimes you can see the eggs through their skin.
The female will release hundreds of bright green-colored adhesive eggs to the underside of floating plants. Instantly, remove the plant to another tank, where you can let the eggs hatch and raise the fry. Otherwise, the loaches will feed on the eggs and any fry.
Eggs will hatch in approximately 24 hours later. The floating plant is home to many enzymes, infusoria, which can be the best primary food for the hatched fry. Additionally, you may feed them brine shrimps and other commercially prepared food that is suitable to newly hatched fry.

Are Kuhli Loach right for you?

If you want to build an aquarium of a peaceful community with various fishes or if you already have one, then you can consider adding Kuhli Loaches.

Like any other fish, you need to create a mimic of their original habitat for Coolie Loaches.
Understanding their temperament and the environment of their natural habitat will help you to recreate close to their original settings.
The other fellow members must be coming from a similar setting in their original home as well. So that all their requirements fall under close parameter settings when it comes down to the substrate, water temperature, hardness, pH, Plants, and most definitely their temperaments.
Then I must say, Kuhli Loach, will be a great addition to your community tank as they scavenge on the leftovers that sunk to the bottom and keep the bottom of the tank clean. Here is a win-win situation for the entire community.
Let us know what you think about our scavenger friend in the comment section. You may contact us for any queries here.

Leave a Reply

Your email address will not be published. Required fields are marked *