The Chinese Hillstream Loach is a most unique looking loach that is gentle and non-aggressive!

The Chinese Hillstream Loach Beaufortia kweichowensis at first sight, suggests some type of flounder. But it is much smaller than most sole type fish, reaching only about 3 inches (8 cm). You will be intrigued when you see this curious loach as it is truly an eye catcher.

It is most often called the Chinese Hillstream Loach, but you may find this fish under a variety of names such as the Butterfly Loach, Hong Kong Pleco, Borneo Loach, Butterfly Hillstream Loach, Borneo Sucker, Chinese Butterfly Loach, Chinese Butterfly Pleco, and Chinese Sucker.

This interesting little fish has a light brown to golden background color that is patterned overall with dark spots. It also has a dark spotted line following the edge of the fins. It is a prime example of a “Sucker Belly Loach”, designed to cling to the rocky bottom of fast moving waters. It is a peaceful little loach with a peculiar stop-and-go type of swimming motion. It can be quite quick, but it will not defend itself against aggressors.

This is a fairly hardy little fish. They do tend to be shy so be sure to provide plenty of hiding places. Because they are from cooler waterways, they will do best in a “river” type aquarium kept with other gentle tank mates. Good water movement along with hiding and resting places created with plants, rocks, and driftwood in will be appreciated. They also love to scavenge debris and graze on algae, even cleaning the glass on the sides of the aquarium. They enjoy the company of their own species and are best kept in a group of five to seven, with the suggested minimum being three.

Scientific Classification

  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Actinopterygii
  • Order: Cypriniformes
  • Family: Balitoridae
  • Genus: Beaufortia
  • Species: kweichowensis

Chinese Hillstream Loach – Quick Aquarium Care

  • Aquarist Experience Level: Intermediate
  • Size of fish – inches: 3.2 inches (8.00 cm)
  • Minimum Tank Size: 20 gal (76 L)
  • Temperament: Peaceful
  • Aquarium Hardiness: Moderately hardy
  • Temperature: 68.0 to 75.0° F (20.0 to 23.9&deg C)
Aquarist Experience Level:Intermediate
Aquarium Hardiness:Moderately hardy
Minimum Tank Size:20 gal (76 L)
Size of fish – inches3.9 inches (10.01 cm)
Temperature:74.0 to 81.0° F (23.3 to 27.2&deg C)

Habitat: Distribution / Background

The Chinese Hillstream Loach Beaufortia kweichowensis (previously Gastromyzon leveretti kweichowensis) was described by Fang in 1931. They are found in Southeast Asia; Hong Kong. Other common names they are know by are Butterfly Loach, Hong Kong Pleco, Borneo Loach, Butterfly Hillstream Loach, Borneo Sucker, Chinese Butterfly Loach, Chinese Butterfly Pleco, Chinese Sucker, and Leverett’s Hillstream Loach.

These fish are found in Xi Jang River system in southern China. They are also found in the upper part of the drainage in Guizhou Province and in Guangxi Autonomous Region and Guangdong Province. These areas of China are becoming a major concern for fish because it is very industrialized and has become very polluted. However it is not listed on the IUCN Red List.

These loaches normally live in the shallow, fast moving rivers and streams. Substrate is normally sand, smooth stones and boulders. Not much aquatic vegetation is present due to the current and substrate. The substrate is often leaf covered. As with most loaches they tend to prefer waters very high in oxygen. Their natural diet is composed of benthic algae and other micro organisms.

  • Scientific Name: Beaufortia kweichowensis
  • Social Grouping: Groups
  • IUCN Red List: NE – Not Evaluated or not listed


The Chinese Hillstream Loach can reach just over 3 inches (8 cm) in length, though it is usually smaller in the aquarium, and has a lifespan of 8 years. This loach is a flat bellied, low profiled fish. Many confuse this fish with a Pleco. Its body is a yellow-brown covered in black polka dots. Its anal and dorsal fins are transparent with opaque strips.

  • Size of fish – inches: 3.2 inches (8.00 cm) – This fish may grow to be somewhat smaller in the home aquarium.
  • Lifespan: 8 years

Fish Keeping Difficulty

This loach can be quite hardy under the right conditions. They are not recommended for beginners however, because of their need for pristine water and they do not have scales. Not having scales make them more prone to disease and very sensitive to medications used to treat disease. Experience in treating scaleless fish is very important to be able to give your loach a healthy and long life.

  • Aquarium Hardiness: Moderately hardy
  • Aquarist Experience Level: Intermediate

Foods and Feeding

The Chinese Hillstream Loach is an omnivore, feeding mainly on benthic algae and other micro organisms in the wild. In the aquarium this loach will generally eat all kinds of live foods, sinking pelleted and tablet foods, flakes, and algae. They like frozen foods as well. To keep a good balance give them a high quality flake or tablet food everyday. Feed mosquito larvae, brine shrimp (either live or frozen), tubifex, daphnia, and some vegetable foods such as algae wafers and mashed peas.

  • Diet Type: Omnivore
  • Flake Food: Yes
  • Tablet / Pellet: Yes
  • Live foods (fishes, shrimps, worms): Some of Diet
  • Vegetable Food: Some of Diet
  • Meaty Food: Some of Diet
  • Feeding Frequency: Several feedings per day

Aquarium Care

For this loach to thrive, it is most important that the water be clean and well-oxygenated. The use of an over-sized filter is a minimum requirement. Weekly water changes of at least 30% are also needed to keep the loach healthy.

  • Water Changes: Weekly – Water changes of at least 30% weekly.

Aquarium Setup

These fish are mostly bottom dwellers, but will be seen grazing on algae on the sides of the aquarium. They will do well in a medium sized aquarium (ideally 20 gallons or so) with plants and places for retreat such as rocks, caves, and roots. The substrate needs to be a fine gravel or sand that does not have sharp edges. They do best in soft, slightly acidic water.

The Chinese Hillstream Loach should have a tank that resembles their natural habitat. They need good water flow and this can be achieved with powerheads or a river manifold. These fish, like most loaches, need ample hiding places that can be constructed with larger smooth boulders and drift wood. Bright lighting is needed to aid in growing algae, but there must be areas of shade for the fish. Live plants aren’t normal to their habitat but do help with water quality. A tight fitting lid is required to prevent escape as these loaches will climb the glass.

It is most important for the health of these fish that the water be clean and well-oxygenated. A high quality canister filter is best and will clean as well as help create water movement. We suggest the use of an over-sized filter as a minimum requirement. Installation of a rivertank manifold is recommended, though not essential, as it would not only provide an excellent alternative/additional form of filtration but bring with it the benefit of unidirectional water movement and more closely simulate what the fish experience in nature. Water turnover should ideally be in excess of 20 times per hour so additional powerheads/airstones can be used to achieve the desired flow and oxygenation in the absence of such a device.

  • Minimum Tank Size: 20 gal (76 L)
  • Substrate Type: Sand/Gravel Mix – Should have larger smooth boulders as well.
  • Lighting Needs: Low – subdued lighting – Can have strong lighting to encourage algae growth but must provide areas of shade for the fish.
  • Temperature: 68.0 to 75.0° F (20.0 to 23.9&deg C)
  • Range ph: 6.5-7.5
  • Hardness Range: 5 – 10 dGH
  • Brackish: No
  • Water Movement: Strong – This fish is accustomed to life in swiftly moving streams, as such it appreciates a strong current and requires highly oxygenated water.
  • Water Region: Bottom – This fish mainly keeps to the bottom although it will happily clean the aquarium walls of any algae growth.

Social Behaviors

A good community fish, they are gentle and peaceful. The Chinese Hillstream Loach will do well with non-aggressive tank mates as well as enjoy other members of their own species. It is recommended that they be kept in groups of at least 3, with larger groups of five to seven being recommended. They are rather shy, but when they move they are quite quick.

  • Venomous: No
  • Temperament: Peaceful
  • Compatible with:
    • Same species – conspecifics: Yes – This fish is very peaceful and is happiest in the company of its own kind. A group of 7 is considered an ideal number although 3 would suffice.
    • Peaceful fish (): Safe – Best if kept in groups of 3 to 7.
    • Semi-Aggressive (): Monitor
    • Aggressive (): Threat
    • Large Semi-Aggressive (): Threat
    • Large Aggressive, Predatory (): Threat
    • Safe
    • Shrimps, Crabs, Snails: Safe – not aggressive
    • Plants: Safe

Sexual differences

Although the sex of these has not been determined, it is reported that males are typically larger than the females.

Breeding / Reproduction

There are reports of the Chinese Hillstream Loach having spawned for hobbyists but not much is known about their breeding habits. They are not yet bred commercially.

  • Ease of Breeding: Unknown – This fish will occasionally spawn in the home aquarium but little is known of its breeding habits.

Fish Diseases

Chinese Hillstream Loach are scaleless and prone to disease, so take caution when introducing these fish to an established tank. The Batik is also very sensitive to medication to treat many diseases; a separate hospital tank is needed. Cold water and condition changes can also cause stress to this fish which makes them even more prone to disease.

An outbreak of disease can often be limited to just one or a few fishes if you deal with it at an early stage. When keeping these sensitive types of fish, it is common to catch deteriorating water conditions and disease before other fish are affected. The best way to proactively prevent disease is to give your Chinese Hillstream Loach the proper environment and give them a well balanced diet. The closer to their natural habitat the less stress the fish will have, making them healthier and happy. A stressed fish is more likely to acquire disease.

Anything you add to your tank can bring disease to your tank. Not only other fish but plants, substrate, and decorations can harbor bacteria. Take great care and make sure to properly clean or quarantine anything that you add to an established tank so not to upset the balance. It is recommended to read up on the common tank diseases. Knowing the signs and catching and treating them early makes a huge difference. For information about freshwater fish diseases and illnesses, see Aquarium Fish Diseases and Treatments.


The Chinese Hillstream Loach is becoming popular and more readily available.



 Beaufortia kweichowensis (Image Credit: Daiju Azuma, Wikimedia Commons CC BY-SA 2.5 Generic)