- Scientific Name: Acantopsis dialuzona
- Synonym: Acanthopsis biaculeata, Acanthopsis choerorhynchus, Acanthopsis choirorhynchos, Acanthopsis choirorrhynchus, Acantopsis choirorhynchos, Aperioptus pictorius, Cobitis choirorhynchos, Cobitis macrorhynchos
- Common Name: Banana Fish, Horseface Loach, Horsehead Loach, Horse Face Loach, Longfaced Loach, Long-nosed Loach
- Family: Cobitidae
- Origin: Southeast Asia
- Adult Size: 8 inches (22 cm), usually smaller
- Social: Peaceful
- Lifespan: 10 years
- Tank Level: Bottom
- Minimum Tank Size: 15 gallon
- Diet: Omnivore, enjoys live foods
- Breeding: Unknown, not successfully bred
- Care: Intermediate
- pH: 6.0-6.5
- Hardness: up to 10 dGH
- Temperature: 75-82°F ( 25-28°C)
During a recent 2012 revision of loaches, the scientific name for the Horse Head Loach was changed from Acantopsis choirorhynchos to Acantopsis dialuzona. However, it is quite common to find it referred to by either name, as well as several older synonyms. They are widely distributed throughout Southeast Asia including; Borneo, Java, Malaysia, Myanmar, Sumatra, Thailand, and Vietnam. This wide distribution has led some to question if this is indeed a single species, or rather a group of closely related species that have not yet been differentiated.
First imported to Europe in 1929, this species is now exported extensively, although it is possible that what is sold as the Horse Face Loach is actually a mix of closely related species, rather than a single species.
To date, they have not been successfully bred in captivity, so all specimens sold in the aquarium trade are wild caught. In the wild, Acantopsis species are found in fast flowing rivers and streams that have a mud, sand or fine gravel bottom.
This rather shy loach has dark spots sprinkled over a yellowish-brown body color.
The color patterns vary somewhat based upon the natural habitat in which the particular fish originated. Elongate in shape, this species has a long tapering snout that resembles the head of a horse, thus giving it the common name of Horse Face Loach. At the end of the snout are three pairs of small barbells. Adults can reach a length of 8 inches (22 cm), but in most cases remain smaller than that. Females are usually larger than males.
The caudal fin of the Horse Face Loach is slightly forked, and the belly is flat and lighter in color than the rest of the body. Like other members of this family, this species is equipped with a pair of extremely sharp spines under the eye orbits. These spines can be extended as a means of defense when the fish is threatened or attacked. Care should be taken when netting this species, as the spines can easily become entangled in the net.
It is quite common for this fish to be hidden much of the time, as they enjoy burrowing in the substrate. They will remain just below the surface of the substrate, with only their eyes poking out to allow them to peruse the activity within the tank. While below the surface they will sift the fine substrate for small particles of food.
Generally this species is a rather slow swimmer, but is capable of making surprisingly quick darts about the tank when startled. This species is predominantly nocturnal.
Generally a peaceful species, the Horse Face Loach may be combined with other peaceful loaches as well as other peaceful species that occupy the middle and top strata of the tank. This includes such species as Barbs, Danios, Rasboras and Tetras. However, this species will do better if they are kept with others of its own kind. Ideally keep at least a half dozen of them together, if space allows. For this reason, they are best kept in larger aquariums. Within their own species group, they will often establish their own hierarchy, and may even establish territories that they will defend. This is another reason for keeping them in a larger aquarium.
When building a habitat for this species the substrate is particularly important. Because they borrow and spend much of their time buried, they must have a fine substrate of either sand or fine gravel. If live plants will be used in the tank, do not plant them with bare roots, as they will be uprooted quickly. Instead, plant them in pots to keep them in place. Sturdy plants such as Anubias are ideal. Another option for live plants is to use floating plants, which also subdues the lighting, something that this species prefers.
Driftwood and smooth rocks can also be used in the décor, being placed in such a way to provide hiding spaces. Good water movement is recommended, as this species requires an oxygen-rich environment. Frequent water changes are necessary, as the Horse Face Loach is sensitive to organic waste. Water should be soft and on the acidic side, with a pH in the range of 6.0-6.5. Keep the temperature between 75-82°F ( 25-28°C). Ideally, the tank should be matured, as this fish does not cope well with the rapidly changing chemistry of a newly set up aquarium.
Because they are more active at night, providing a moon light is a good way to get an opportunity to observe these fish. Once the primary lighting is off, they sometimes will come out in the dim light and more actively forage for food. Dropping a bit of sinking food in the tank after the main lights are off will help nudge them to come out of their hiding spots.
Relatively easy to please, this species will eat most foods that are offered. However, they particularly enjoy live foods, being accustomed to small crustaceans and insect larvae in their native habitat. Offering a varied diet will keep them in optimal health. Because they are bottom feeders, make sure that food is reaching the bottom. This may require providing sinking foods in addition to other types of food. Live or frozen brine shrimp, mosquito larvae, daphnia, tubifex, and bloodworms are all good options for this loach. Supplemental algae wafers or tablets are welcomed as well.
There are very few clear cut sexual differences between males and females other than size. In males, the first few branched rays of the pectoral fins are extended. However, that subtle difference is not always easy to spot, especially when the fish spends much of its time buried in the substrate. Adult females will typically be larger than males, and will also be rounder. The size difference is most noticeable difference between the sexes.
There have been no documented instances of this species having spawned in captivity. This includes commercial breeding as well. All specimens sold in the aquarium trade are wild caught.