The Torrent Loach Homaloptera Bilineata is really handsome, but a rare find to the aquarist!

The Torrent Loach Homaloptera Bilineata is just one of several species in the Homaloptera genus that is known as a Torrent Loach. Being as handsome as it is, it will hopefully become more available and earn a common name. These fish are also commonly known as a Lizard Loach and Gecko Loach. As a fish becomes more familiar, someone will eventually dub it with its own name, and once coined, that will become its common name. And of course, sometimes a fish will end up with numerous common names!

The loaches in the Homaloptera genus have been known as Torrent Loaches, and sometimes referred to as ‘gecko’ or ‘lizard’ fish, because of being especially designed to cope with living in fast waters. They come from cool fast-moving, often torrential streams, and are able to cling to various surfaces. There are several in this genera that are more common to the aquarist such as the Saddle Back Loach or Clown Torrent Loach Homaloptera orthogoniata. or the Clown Torrent Loach.

Similar to the other Torrent Loaches, the Homaloptera Bilineata, has a brownish red background coloring. It has strong dark, rather blotchy markings running horizontally along the top, from the dorsal fin through the tail fin. It is similar to the Saddle Back Loach H. orthogoniata which also has a pair of dark stripes running through the eyes and back around the dorsal fin, but from here the black markings vary. These two loaches differ in that the markings around the dorsal fin on the Saddle Back spread down lower giving it more of a ‘saddle’ appearance.

The H. bilineata Loaches will do best in a cooler “river” type aquarium with good water movement, subdued lighting, and regular water changes. Provide a fine gravel or sand substrate that does not have sharp edges. Be sure to provide plenty of hiding and resting places created with round river type rocks and driftwood. A moderate amount of plants can be a nice addition but leave a large open area for swimming.

They are peaceful community fish and enjoy other less aggressive tank mates. They also 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


Torrent Loach – Quick Aquarium Care

Aquarist Experience Level:Intermediate
Aquarium Hardiness:Moderately Difficult
Minimum Tank Size:30 gal (114 L)
Size of fish – inches3.9 inches (10.01 cm)
Temperature:68.0 to 78.0° F (20.0 to 25.6&deg C)

Habitat: Distribution / Background

The Torrent Loach Homaloptera Bilineata was described by Blythe in 1860, and is found in Asia. This loach can be found in the Sittaung River in south central Myanmar and in the Salween River basin in Myanmar. It is also found in northwestern Thailand and in the Mae Kling system in Thailand. There are few reports that this loach also inhabits Nepal. It is also sometimes referred to as a Lizard Loach or Gecko Loach. H. Bilineata is not listed on the IUCN Red LIst.

H. Bilineata inhabits swift flowing streams and headwaters containing clear and highly oxygenated water. They can often be found in riffles and runs and typically stay in shallower waters. The substrate of their environment is usually made up of gravel, sand, rocks, and boulders covered with algae and other micro organisms. Aquatic plant life is normally not present because of the swift moving waters. This loach is a specialized grazer and feeds on biofilm, insect larvae, and other invertebrates.

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


Similar to the other Torrent Loaches, the Homaloptera Bilineata has a brownish red background coloring. It has strong dark, rather blotchy markings running horizontally along the top, from the dorsal fin through the tail fin. It is similar to the Saddle Back Loach H. orthogoniata which also has a pair of dark stripes running through the eyes and back around the dorsal fin, but from here the black markings vary. These two loaches differ in that the markings around the dorsal fin on the Saddle Back spread down lower giving it more of a ‘saddle’ appearance.

This loach can get up to 4 inches (10 cm) in length in the wild, but doesn’t usually attain the highest length in captivity. The aquarist should not be surprised if their Torrent Loach reaches only just over half of this length in the aquarium.

  • Size of fish – inches: 3.9 inches (10.01 cm) – These fish can reach between about 2 1/2 – 4 inches (6.25 – 10 cm) in the wild, but are usually on the smaller side in the aquarium.
  • Lifespan: 5 years

Fish Keeping Difficulty

The Torrent Loach can be hardy under the right conditions. Take caution when traveling with these fish as they do not transport well. They are not recommended for beginners 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 Difficult – This fish does well when it is settled, although it is quite delicate during and shortly after transport.
  • Aquarist Experience Level: Intermediate – These Loaches need pristine waters with a high oxygen content. Because they are prone to disease and are very sensitive to the medications that will treat them, a more experienced fish keeper is suggested.

Foods and Feeding

The Homaloptera Bilineata Loach are omnivores They are specialized grazers that feed on biofilm, insect larvae, and other invertebrates in the wild. In the aquarium they 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.

Feed live or frozen bloodworms, daphnia or artemia is essential to the longterm health of this loach. It is recommended that the tank contains solid surfaces that will aid in the growth of algae and other aufwuchs which will give this loach the need nutrients not always found in processed foods.

  • Diet Type: Omnivore
  • Flake Food: Yes
  • Tablet / Pellet: Yes
  • Live foods (fishes, shrimps, worms): Some of Diet – These foods are needed to keep your loach healthy, bloodworms are a great choice.
  • Vegetable Food: Most 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 about 30% are needed to keep the loach healthy. With your weekly water change make sure to vacuum the gravel to remove all excess food and waste. Make sure not to remove the biofilm from the rocks, decor, or glass other than the viewing panes of the tank. A magnet algae cleaner normally does a great job in keeping the viewing pane clear.

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

Aquarium Setup

These fish are mostly bottom dwellers. Because these fish do best in groups, a larger tank will work best, at least 30 gallons. The tank needs to have ample hiding places for this shy fish to retreat such as rocks, caves, and roots. They do best in soft, slightly acidic water.

It is recommended to have a tank set-up that resembles its natural habitat, slow moving rivers. The substrate should be sandy or small smooth gravel. Larger smooth rocks should be used as hiding places. Driftwood and branches should be added to provide shade and places for quick retreat. Java Ferns can be introduced and will attach to the decor. Powerheads or a rivertank manifold can be added to provide a unidirectional flow to simulate its natural habitat. Be sure to have ample smooth surfaces to encourage biofilm to grow.

The most important thing for these loaches is that they always have clean and well-oxygenated water. An over sized filter will meet that requirement. The tank water should turnover at least 10-15 times per hour. Powerheads and airstones can be introduced to help achieve proper flow and oxygenation.

  • Minimum Tank Size: 30 gal (114 L)
  • Suitable for Nano Tank: No
  • Substrate Type: Sand/Gravel Mix – Should have larger rocks and boulders to provide surfaces for biofilm to grow on.
  • Lighting Needs: Low – subdued lighting
  • Temperature: 68.0 to 78.0° F (20.0 to 25.6&deg C)
  • Range ph: 6.5-7.0
  • Hardness Range: 2 – 12 dGH
  • Brackish: No
  • Water Movement: Strong
  • Water Region: Bottom – These fish are mostly bottom dwellers.

Social Behaviors

A good community fish, they are not aggressive fish at all, but due to their requirements it is best to house them with fish from similiar environments like Barilius, Discherodontus, Garra, Devario, some Rasbora and gobies and Oreoglanis catfish. Other families of loaches are usually fine as well, although they may engage in harmless fights.

These loaches in nature are found living in aggregations so it is best to keep 6 or more. Keeping them singly or just in pairs will cause them stress and they will withdraw into hiding more often. These loaches will interact with each other in close packs. Groups will alternate in facing currents at different times of the day. Very interesting to watch them.

  • Venomous: No
  • Temperament: Peaceful
  • Compatible with:
    • Same species – conspecifics: Yes – This fish likes to be housed with its own kind, ideally in groups of three to seven.
    • Peaceful fish (): Safe
    • Semi-Aggressive (): Monitor
    • Aggressive (): Monitor
    • Large Semi-Aggressive (): Monitor
    • Large Aggressive, Predatory (): Monitor
    • Safe
    • Shrimps, Crabs, Snails: May be aggressive
    • Plants: Safe

Sexual differences

Sexually mature females are usually a little larger and fuller-bodied than males.

Breeding / Reproduction

They are not yet bred commercially, and there are no reported aquarium spawnings. In nature these loaches are seasonal spawners.

  • Ease of Breeding: Unknown

Fish Diseases

The Torrent Loaches are scaleless and prone to disease, so take caution when introducing these fish to an established tank. The Torrent Loach 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.

Loaches are more susceptible to disease than other aquarium fishes, which may have to do with the faint body scales and no head scales. The most common disease that this loach is susceptible to is Ich. Ich is short for Ichthyophthirius, also known as “white spot disease”. It is a parasite that can attack nearly all aquarium fishes, but you’ll find that loaches are often the first to be attacked. Take great care in treating ick as loaches are very sensitive to the medications used to treat it. Often the dose is half of what is normally used.

The second most common thing that affects loaches is something called skinny disease. This can be diagnosed fairly easily. If your loaches are eating a nutritious diet and in healthy amounts, and still seem to be loosing weight, there is a good chance they have skinny disease. This disease is caused by internal parasites and can be treated with medication if used carefully.

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 Torrent 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 Torrent Loach Homaloptera bilineata are only rarely available, but make a very interesting addition to the aquarium when you obtain them.



 Homaloptera bilineata (Image Credit: S. Kulabtong, Wikimedia Commons CC BY-SA 3.0 Unported)