Kuhli Loach: The Ins and Outs About This Freshwater Fish

Kuhli Loach

Kuhli Loach (Pangio Kuhli) is an adorable scavenger fish with a peaceful temperament. 

This fish can add more beauty to your aquarium and are considered as “Charming Cleaners” (because of their scavenging nature). Surprisingly, these tiny fish are quite fascinating because they resemble the snakes.

We will discuss some important points regarding the care and management of this friendly fish.

Scientific Details


Other names of Kuhli Loach are ‘Throne Eye Fish” Water Noodles, Underwater Noodles, Underwater Snakes, Coolie Loach, Slimy Cinnamon Loach, and Giant Coolie Loach, etc.

Scientific synonym: Acanthophthalmus kuhlii

Acanthophthalmus meaning thorn eye/prickle eye. Since they have spines underneath their eyes.


Kuhli Loach is freshwater fish. This fish originated from Indonesia and the Malay Peninsula, southwestern area of Thailand, West Malaysia, and the southeastern part of Myanmar (Burma), and Singapore.

Physical Appearance:

Kuhli Loaches are freshwater fish with a particular eel-like slender body shape. They have beady black eyes along with barbels (sensitive feelers used for food foraging) around their mouth.

There are many species of Kuhli Loach with various charming colors. But Pangio Kuhli specifically has dark brown/pinkish-yellow bands.

They have very tiny fins (nearly invisible). But with keen observation, it becomes clear that males have larger pectoral fins (more paddle-shaped, also having some pigments in them) and more musculature over the dorsal cross-section of the body.


There are so many species of Kuhli Loaches. Every species has its own characteristics, requirements, and growth pattern.

Some important species have been given below:

  • Pangio  Anguillaris (Silver Kuhli)
  • Pangio Oblonga (Black Kuhli or Chocolate Kuhli Loach)
  • Pangio Semicincta
  • Pangio Shelfordii
  • Pangio Rubiginosa

Note: it is important to know that Pangio Kuhli is commonly kept fish in aquariums all around the world.


Kuhli Loaches are known as ‘bottom dwellers. In a natural environment, they love to stay in muddy/sandy beds with slow-moving rivers and streams. They love the tropical environment (decaying plant matter, low light, a great amount of debris).


In the wild, this fish grows up to nearly 5 inches. On the other hand, in aquariums, it reaches the size of around 2.5 to 3.5 inches.


This fish has a surprisingly long lifespan. But this highly depends upon the way you take care of them (proper management/nutrition/a comfortable environment). These fish can live from 10 to 14 years.

Factors that decrease the lifespan:

Key factors which badly impact the longevity of this charming fish have been given below:

  1. Poor management
  2. Stressful environment (inferior quality tank water)
  3. Poor nutrition (inadequate supply of all essential nutrients which help in better growth and performance of this fish)

Disease Susceptibility:

According to scientific literature, Kuhli fish are susceptible to several diseases. The main reason is their scale-free body (very rare scales on their body and a scale-free head).

Plus, they also show sensitivity to a variety of medications. This is why it is highly recommended to keep them stress-free and provide them optimal living conditions.

Compatibility Status:

These tiny creatures are very friendly and love to stay with other aquatic creatures. This is your responsibility to select safe tank mates (with which Kuhli feel relaxed and stress-free.

Selection of its tank mates depends upon many factors but some important aquatic organisms have been listed below, which could be the best option to keep along with Kuhli in the same tank. Kuhli Loaches can easily adapt to these fish who love to stay on the surface. 

Neon Tetras and Black TetrasHoney Gourami and Dwarf GouramiRed Cherry Shrimps
Zebra Danios and Pearl DaniosCorydoras/HatchetfishRed-Tailed Black Sharks and Oto catfish
Harlequin Rasboras/ GuppiesRainbow Fish/ ApistogrammaClown Loaches/White Cloud Mountain Minnows.

*Pelagic fish are those fish that live in the middle (neither bottom nor surface). This is why; pelagic fish are considered the ideal tank mates for Kuhli.

Tiger BarbsBlue Gourami

On the other hand, don’t keep the following fish with Kuhli in a shared tank:

ArowanasCichlids/Monster FishChinese Algae Eaters

Note: It is also not considered good to keep snails with Kuhli because they are highly likely to gobble them up.

Note: Kuhli Loaches are calm and non-aggressive fish. When they grow bigger, they may eat shrimp if kept together with them. Avoid keeping territorial fish with Kuhli as they can provoke aggression in your Kuhli.


Social Fish:

Interestingly, Kuhli Loaches are considered ‘Social Fish’. They become active and playful when kept with their fellow fish species.

Usually, it is a good idea to keep Kuhli in groups (minimum group of five species) or as per the accommodating capacity of the tank. If you keep Kuhli alone, they will become stressed.

Aquarium Environment:

This plays an important role in the overall well being and best performance of Kuhli. The environment of the aquarium should possibly mimic the natural environment of the Kuhli.

                                 GOOD SUBSTRATE EQUALS HAPPY KUHLI

Bottom Bedding:

This must be made upon a smooth substrate (a mixture of sand and gravel). It is important to keep in mind that the substrate should not be jagged. It must be clean and clear.

Preferably, Kuhli stays happy resting on large smooth stones and rocks. In addition, some suitable plants should also be set up there. As you know, Kuhli is an adventurous and explorative fish. They like caves, crevices, and other hiding places (this is a very important point to remember).

Note: Never place any sharp objects or hard gravel in your tank.

Best Plants for Kuhli:

Some best plants for Kuhli Loach have been given below:

Note: It is better to choose plants that require low light. Provide hiding spaces for Kuhli in the tank so they can chill out and have a quiet time.

Tank Size:

This is a very important parameter. Ideally, its capacity should be 20 gallons (75.7 liters). Additionally, this also depends upon the number of Kuhli to be accommodated. For each additional Kuhli, you’re advised to increase the tank capacity by 3 gallons.

Tank Shape:

Preferably, the tank should be long and rectangular. Nothing fancy here.

Kuhli likes well-oxygenated aquariums. It is recommended to keep aquariums clean and oxygenated. Appropriate adjustments of water currents should be observed. Also, there must be careful and considered placement of filters.

Note: Change the tank water weekly (minimum 30%), immediately remove the excess feed after feeding. Remove waste material regularly (as Kuhli loves a clean environment). It is recommended to vacuum the gravel weekly.

Water Parameters:

Water plays a prime role in keeping Kuhli healthy and active. By default, Kuhli likes good quality water. Some important parameters of water (to be used in an aquarium) have been given below:

pH5.5-7.0 (Kuhli prefer acidic pH)
Temperature24-29 ºC (75-85 F)
GH (General Hardness/Water Hardness)3-5 GH  (50-83 ppm)
Quality  Ammonia ContentSupreme (Neat and Clean) 0
KH/CH ( Carbohydrate Hardness)3-4 dKH (53-71 ppm)
Nitrate30-40 ppm

Note: Kuhli Loaches are tropical fish. They love warm water with very low hardness and slight acidity. It must be the top priority of the owner to provide all essential water parameters for Kuhli to ensure their optimum growth and wellness.

Remember, the water flow rate should be moderate because they like slow-moving rivers and streams. Heaters can be installed in the tanks to maintain a healthy temperature.

Light Management:

Light is an important factor that impacts the breeding and overall performance of Kuhli Loach. Kuhli Loaches are nocturnal fish (they become active during night time).

They don’t like bright light and keep themselves hidden during the daytime. This is why it becomes hard to see them during daylight hours. However, when there is dim light, it becomes easier to notice Kuhli. Low or dim light is preferred by Kuhli Loach.

Nutritional Considerations:

A well-balanced diet plays an important role in promoting the overall health of Kuhli Loach. Basically, Kuhli Loaches are omnivores (they can feed on both plants and animals).

Ideally, their diet should be protein-dense and contain all essential growth-promoting nutrients from both animal and plant sources.

Natural Diet & Important Nutritional Considerations

In their natural habitat, Kuhli Loaches prefer eating live organisms. Some of them have been listed below:

  • Bloodworms
  • Flies
  • Mosquito larvae
  • Plant matter

In captivity, it is a great idea to feed them a combined diet (live food, vegetables, processed food).

It is fine to feed Kuhli commercially available fish diets. But be careful, processed diets must be free from grain because grain feeding can cause a number of health issues in Kuhli (eg. bladder problems).

Additionally, frozen foods can also be fed to Kuhli. Kuhli is night feeders/scavengers. Remember that the feed should sink because if it floats on the surface, Kuhli won’t be able to eat it because they are bottom dwellers.

Special Foods for Optimum Health

Fresh vegetables such as cucumber, courgettes are good options. Along with that, other foodstuffs such as microviers, brine shrimps, tubiflex, and small crustaceans can also be served as additional health-promoting diets.

Feeding Frequency:

It totally depends upon you. But it is highly recommended to feed Kuhli several times in a day. Additionally, don’t forget to feed them during night hours and before sunrise.

Breeding Guide:

Breeding is a very critical stage for Kuhli. During this, Kuhli needs a lot of attention and careful management. Being a responsible owner, this is your responsibility to provide a stress-free and well-equipped breeding tank.

Remember, spawning (an act of discharging eggs) only occurs in a comfortable aquarium environment.

These following points should be kept in mind for successful breeding:

  1. Dense vegetation and floating plants with roots must be in the aquarium (females preferably lay eggs in plants).
  2. Temperature is another key variable that helps in successful spawning and breeding. The best breeding temperature is about 28 ºC. Additionally, lower the water level in the tank and maintain acidic pH.
  3. Light is also an important parameter. For a successful breeding outcome, it must be kept as low as possible. Dim light triggers spawning in a better way.
  4. Fish feed must be present in the aquarium all the time, especially during breeding. Remember, diet also plays an integral role in encouraging spawning. (Preferably live food should be given).
  5. Last but not least, try keeping the same species of Kuhli fish together, as they feel more comfortable with each other.

Note: Females become larger/heavier during breeding. They produce green colored eggs. Sometimes, their ovaries can be easily observed through the skin during breeding.

Health Care Guide:

Good health management is another important parameter to be maintained while raising Kuhli in aquariums. Kuhli Loaches are more susceptible to several diseases. So, they need extra health care.

The most frequently seen health condition in Kuhli Loach is white spot disease (itch). In this condition, white spots, raised lesions (which are usually small and blister-like) are observed on the skin and fins of the fish.

The major cause of this itch is a ciliate protozoan (Ichthyophthirius multifiliis). It is better to treat this condition as early as possible if spotted.

Other parasitic infestations also occur in Kuhli loaches which make them skinny/underweight and cause stress in them.

                                   PREVENTION IS BETTER THAN A CURE

Try to provide Kuhli a healthy and stress-free aquarium environment. Provide them with good quality water and a balanced diet. By providing quality living conditions for Kuhli, a wide range of diseases can be prevented.

Note: Only use medication after proper consultation with a registered veterinarian.

Quick Insight

NameKuhli loach (Pangio kuhli)
Level of careIntermediate (require high-quality water with optimum pH and temperature and appropriate bedding)
Age of maturity/sizeApprox 2 years/ 3-5 inches
Life span10-14 years (depends upon the care and management.
Egg colorGreen colored
TemperamentFriendly, non-aggressive
Mode of nutrition/preferred living siteOmnivores/bottom dwellers/scavenger
(usually prefer high protein diet)

John Kilmerstone

I love keeping pet fish and receive a lot of joy and peace from watching these colorful creatures. Please visit this website and explore the wonderful world of pet fish. Discover how to care for and look after pet fish and amplify your satisfaction.

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