Kuhli Loach | A to Z Guide – Care, Tank Mates, Size, and Diet

ByDelia Heiman Updated

(Credits to Iidkk)

Kuhli loaches have various names, such as coolie loach, leopard, or slimy loach. There are two subspecies of kuhli loaches known as Pangio kuhli sumatranus and Pango kuhli myersi that differ in appearance, especially in colors and markings.

Overview/Origin

Kuli loaches are commonly found in the freshwater streams of Southeast Asia (particularly in Malaysia and Thailand, Singapore, and Borneo.

Moreover, it had three scientific name revisions, from Cobits kuhli to Acanthophthalmus kuhli and Pangio kuhli (currently). 

Kuhli loaches are among the tropical fishes that appeared and were classified in 1846. It belongs to the Cobitidae family, typically known as an Old-World freshwater.

Kuhli loaches are considered to be friendly and peaceful-dwelling fish. It serves as an owl’s counterpart in the wilds, scavenging for food at night. Known as a temperate species, it can be an additional pet fish to fish enthusiasts.

There are ten common species of loach fish among 1,043 recorded species listed in 111 genera, split between 10 families, which are as follows:

  • Kuhli loach
  • Yoyo loach
  • Zebra loach
  • Chain loach
  • Stone loach
  • Clown loach
  • Weather loach 
  • Pond loach 
  • Panda loach
  • Hillstream loach

However, not all of these fishes are suitable in your aquarium. 

Appearance

(Credits to Marrabbio2)

Kuhli loach is like an eel-shaped fish with different color variations from yellow to pink. It also has multiple color patterns ranging from brown to dark-colored stripes surrounding its half or nearly the entire body. 

Besides, kuhli loaches have small dorsal fins closely located in their tail. They also have no head scales, and they’re relatively tiny in nature.

A thin transparent skin covers the eye of kuhli loaches, and its mouth is located at the bottom with four pairs of barbels used to catch food. 

There are also sharp fins situated below the eye, which arise when they’re threatened by predators. Its biological feature aided its second scientific name as Acanthopthalmus kuli, also known as “prickle-eye.”

Behavior and Temperament 

Are Kuhli loaches aggressive?

Kuhli loaches are a non-aggressive type of fish species. With their peaceful behavior, kuhli loaches are more active at night than other pet fish (like demersal fish). 

Loaches tend to be shy and wander alone. Further, it is essential to keep kuhli loaches in a home tank that contains fish species with the same temperament. 

They’re not a typical type of schooling fish, but they are comfortable with having companions. They don’t want to move around uniformly, even in an aquarium or in the wild. They’re also busy hunting their food in the soft and muddy ground. 

Lifespan

How long do Kuhli loaches live?

Kuhli loaches can live up to 10 years or more. Still, it depends on how much you treat them in captivity. It’s essential to set the proper environment for kuhli loaches to be comfortable in their aquarium with enough food supply.

Common Diseases

With a tiny and slim body, it’s no wonder that kuhli loaches are prone to diseases. Here are the common conditions you have to look after:

  • White spot disease (Ich). Although this is commonly addressed to most tropical fishes, kuhli loaches are more vulnerable to this disease, knowing that kuhli loaches do not have head scales. Setting the specific temperature range between 73 and 86° Fahrenheit and adding salt is a good treatment for this disease. Regularly changing the water limits the occurrence of this disease as well.
  • Parasite-prone diseases. Since kuhli loaches are tinier, parasites can affect their metabolism. If you see no progress in loaches eating food from time to time and losing some weight, giving them prescribed antibiotics will ease the infection. 
  • Pseudomoniasis (bacterial infection). A common symptom of this disease is ulceration or bleeding. Injecting antibiotics (like Kanamycin and Tetracyclines) can cease the condition.
  • Swim bladder disease. Also known as a flip-over disease, it is primarily caused by buoyancy. Kuhli loaches might suffer or struggle to maintain a normal position while at the tank if they’re infected with this disease.

Size

How big do Kuhli loaches get?

Typically, the kuhli loach’s size ranges from 3 to 4 inches. As they reach full maturity, it grows up to 5 inches (which is rare). Thus, they consume less space in the aquarium.

Meanwhile, male and female kuhlis have two distinct features. Male kuhlis have a more prominent pectoral and muscular dorsal than woman kuhlis.

How many Kuhli loaches can be kept in the tank?

With their small size, you can keep between 4 to 6 kuhlis in a 20-gallon tank. As a rule of the thumb, add 3 to 5 gallons in the tank for every kuhli loach added. 

Remember that the more peaceful the aquarium gets, the more comfortable the environment is for the kuhli loaches. 

Kuhli Loaches Care

(Credits to Robert Mollik)

Tank Size

Further, a suggested ratio of one kuhli loach to 3 to 5 gallons of water is recommended when keeping this fish species in your tank. 

Nonetheless, the minimum tank size would be 20 gallons, enough to let you keep 6 kuhli loaches.

Tank Setup

Setting your home tank with a comfortable habitat for kuhli loaches is essential. It’s where they can live and breed harmoniously, and prioritizing these factors will help you create a friendly setup:

  • Cover or lid. Keeping kuhli loaches’ aquarium closed is essential as they have the tendency to jump out of the water. 
  • A mesh or a sponge in water filters. These filters serve as pivotal support of their inlet tube to limit the loaches getting inside the water filter. Some kuhli loaches owners tend to lose their pet fishes only to find out that they are still alive in the filters.
  • Decoration. Loches tend to hide during the day. It’s advisable to create an environment where there are places kuhlis can hide. Thus, setting the fish tank with driftwoods, rocks, caves, and plants will make them happy. 
  • Large pebbles are not advisable. Setting the tank with more large pebbles is not advisable as it may damage kuhli loaches. Having fine sand in the tank is highly preferred.
  • Low-spirited lighting. A dimmed luminescence lighting would be enough to monitor kuhli loaches’ activities.
  • Soft tap water or water heater. Kuhli loaches prefer a moderate amount of heat to survive. If soft tap water is not available, setting a water heater is highly encouraged because they wouldn’t survive in a cold environment.
  • Filtration. Kuhli loaches enjoy a medium type of water movement that can at least perform 10 times of turnover. 
  • Plants. Floating plants and bottom-embedded plants are necessary for the kuhli loaches. Java moss, Java fern, and Anubias attached to the hard surface of the aquarium are helpful. Encouraging kuhli loaches to come out of their tiny houses can also help by setting floating plants such as duckweed and hornwort.

Water Conditions

Just like other pet fishes around, it’s advisable to mimic kuhli loaches’ natural habitat. Since they’re considered to be freshwater fish (and are likely prone to diseases), make sure to keep these water parameters at the following levels:

  • Temperature. It’s essential to set frequent water changes to maintain its environment and good oxygenation with an average of 73° to 86° Fahrenheit (22° to 30° Celsius).
  • pH range. In terms of pH levels, keep it between 6.0 to 6.5 for consistency.
  • Hardness (dH). The recommended dH level for keeping Kuhli loaches is between 5 to 10.

Diet and Feeding

What do Kuhli loaches eat?

Kuhli loaches are omnivorous, meaning they’ll eat meat and a plant-based diet. They’re not picky in general, but several aquarists report kuhlis prefer more meat. Yet, giving them a balanced diet is recommended for their growth and survival.

What’s more, aquarists find it challenging to feed kuhlis since they’re more active at night. But if you feel like changing the feeding schedule to daytime, it will take kuhli loaches weeks to adjust. 

Still, feeding kuhli loaches at night is more preferred. In essence, feeding kuhli loaches with big fishes does not benefit them for growth, unlike other freshwater fishes.

Mostly, kuhli loaches as a type of freshwater fish and enjoy eating the following:

  • Brine shrimp
  • Sludge worms
  • Bloodworms 
  • Glassworms

Giving them the right amount of food is an effective way to maintain their diet. Kuhli loaches prefer to eat live foods, especially brine shrimp. 

Growing brine shrimp can be done through another safe or small aquarium to ensure that the loaches do not suffer from food shortages. Appending to flakes and frozen foods is the next best option if the foods mentioned are unavailable.

How often should I feed my Kuhli loaches?

You should feed kuhli loaches twice a day, with meals consumable in a span of 2 to 3 minutes. Giving the right amount of food must be well-assessed, or else excessive food can pollute your home tank. 

Nevertheless, their food intake changes as they grow older.

How long can Kuhli loaches go without food?

Adult kuhli loaches can survive without food for the next five days. 

Tank Mates

Having sufficient aquarium size must also have an adequate amount of water. While the minimum size would be a 20-gallon tank, adding 3 gallons for an added kuhli is ample.

Ideally, kuhli loaches are fond of having companions. Being together with peaceful fishes around the aquarium limits them from raising their sharp fins. Examples of delicate fish include:

  • Chili Rasbora
  • Harlequin Rasbora
  • Diamond Tetra
  • Glowing Tetra
  • Zebra Danios
  • Bristlenose Pleco
  • Dwarf Gourami
  • Guppy Fish

If you’re eager to add more pet fishes to the aquarium, keeping non-aggressive fish species is advisable. Putting the aggressive fish in a separate aquarium is recommended.

Breeding

Breeding kuhli loaches are considered one of the most challenging parts of fishkeeping. In principle, setting the proper environment is essential. It’s suggested to establish a breeding tank with the following conditions: low-water levels, dim lights, and floating plants. 

Breeding happens in captivity, and waiting for at least two years before sexing must instill a lot of patience.

Fortunately, Kuhli loaches are communal breeders in nature and don’t have a compelling mood to reproduce. 

The more comfortable kuhlis are, the more efficient for them to breed. Since kuhli loaches are primarily identical, you can spot pregnant kuhlis by their size. You’ll also notice green-colored eggs in a female kuhli’s abdomen.

Several types of fish species might eat the fry and eggs. To prevent this, it’s recommended to separate breeding kuhlis in another tank to have a greater chance of successful spawning.

Since eggs are green in nature, pay attention to the floating plants. Besides, differentiating eggs and plants must be carefully infused.

Hatching the kuhli loaches eggs may take 24 hours. As it grows, they can feed on infusoria (present in live plants). Supplying them with brine shrimp or flakes-food as they grow is recommended. 

Summary

Having a non-aggressive pet fish in the aquarium makes a peaceful environment, like the kuhli loaches. 

Furthermore, knowing kuhli loaches’ behaviors and adapting mechanisms is essential if you want to keep them in your home tank.

To sum up:

  • Setting the tank and its habitat is as important as onboarding other species in the aquarium. Since kuhli loaches are generally quiet and shy in nature, limiting the threat is necessary.
  • If you initially have other species around, don’t instantly add kuhli loaches to the tank. They must be kept in an environment with similar behavior and temperament.
  • Kuhli loaches tend to eat more live organisms (such as worms and shrimps).
  • It’s essential to monitor the overall behavior of the kuhli loaches. By the time the pet fish is not properly digesting any food, ensure to spot any symptoms as they will have possible illnesses to go through.

Meanwhile, it’s highly recommended to separate the fishes to another tank when breeding kuhli loaches. Make sure you meet all the tank requirements and water parameters to have proper spawning.

Lastly, pet fish breeding may not sound easy but knowing these factors will keep your pet groove in their tanks, and so you are outside! Happy breeding!