Classic Car Intelligence
  • Species: Hypoptopoma gulare

  • Species: Hemiloricaria lanceolata

  • Species: Botia dario

  • Species: Ambastaia nigrolineata

  • Species: Labeo cyclorhynchus

  • Species: Protomyzon pachychilus

Loaches and Catfish at WaterZoo

09 February 2018


The readers of Practical Fishkeeping Magazine have consistently voted The WaterZoo one of the best aquarium shops in the country, and with good reason. It's a big store with impressive selections of coldwater, tropical and marine fish. Staff are very well trained, and the store is famous for the quality of information it offers to prospective purchasers, making it a particularly good store for those aquarists just starting out in the hobby.

In this month's round-up we'll look at some catfish, loaches and other bottom-feeding fish currently in stock at The WaterZoo. For more about the store, visit The WaterZoo page elsewhere on this site.

Horseface Loach, Acantopsis dialuzona

This robust, streamlined loach gets fairly big, around 15-20 cm under aquarium conditions, and in the wild specimens as long as 30 cm have been recorded. It is a burrowing species that really should only ever be kept in an aquarium with a soft, sandy substrate. Any plants used in its tank should be able to tolerate this sort of behaviour, with epiphytes and floating plants being the obvious choices.

The Horseface Loach is found in fast-flowing rivers and appreciates a tank with plenty of swimming space and a decent current. Water chemistry is relatively unimportant, this being one of the few loaches known to occur in slightly brackish water, but water quality does need to be good. It is quite peaceful and works well with active midwater fish such as barbs and characins that appreciate similar conditions. It will eat sinking micro-pellets, krill and bloodworms that it can sift out of the substrate, but might consume very small fish, such as livebearer fry, that it comes across during the night. Horseface Loaches are best kept singly unless there is sufficient room to allow five or more specimens to live together amicably.

Note that until recently this species was known as Acantopsis choirorhynchus, but the correct name now appears to be Acantopsis dialuzona. On the other hand, Acantopsis octoactinotos is not the same thing at all. Acantopsis octoactinotos is smaller (around 10-12 cm long) and has a differently-shaped snout that doesn't bend downwards as it does on the true Horseface Loach. It is also less of burrower and tends to be more aggressive, and therefore not such a good community fish.

Black Lined Loach, Ambastaia nigrolineata

This little loach is closely related to the Dwarf Loach Ambastaia sidthimunki, but differs in its colouration. Whereas the Dwarf Loach has vertical as well as horizontal black markings, resulting in the distinctive 'chain' colouration from which arises it alternate common name, Chain Loach, the Black Lined Loach really only has the horizontal stripes, with only the merest hint of the vertical banding apparent on the flanks.

In other regards the two loaches are very similar. Water chemistry is not critical but the water should be clean and not too warm, 22-25C being recommended. A brisk current that ensures plenty of oxygen is a must. As such, they're obvious companions for other active species that enjoy low-end tropical conditions such as Danios and Minnows. With a maximum length of around 7 cm, these are among the smallest botiine loaches kept by aquarists, but they are quite hardy once settled in, and will consume all the usual dried and frozen foods readily. As with most other loaches, plant-based foods, such as sinking algae wafers, are probably important for long-term health. Finally, note that Black Lined Loaches are very sociable and gregarious, and need to be kept in a group of at least six specimens.

Queen Loach, Botia dario

Also known as the Bengal Loach, this is one of the classic botiine loaches, though perhaps kept less often now than it was in the past. It's rather similar to the much bigger Clown Loach in needs and personality, but its smaller size, up to 12 cm, make it a much easier species to house. While it lacks the vivid orange and black bands that make Clowns so popular, these bronzy-brown and mustard yellow markings seen on Queen Loaches are every bit as attractive.

These loaches inhabit the deep rivers of Bangladesh and appreciate warm water that is not too hard; 24-28 C, pH 6.5-7.5, 2-15 dH is recommended. While they do like warmth, like most loaches they are sensitive to poor water quality, so robust filtration and regular water changes are going to be necessary. Queen Loaches are as social and gregarious as Clown Loaches, so keep at least five specimens, but they are otherwise undemanding. They will ignore all but the smallest tankmates, preferring to consume algae wafers, sinking catfish foods, and all the usual frozen invertebrates. They get along well with active fish that leave them alone, barbs and characins being the obvious choices. As with other botiine loaches, they are a bit too boisterous, and sometimes overtly nippy, to be good companions for Angelfish, Gouramis, and other slow-moving, long-finned fish.

Harlequin Shark, Labeo cyclorhynchus

While often considered loaches of a sort, the cyprinids we call 'sharks' are a mixed bag of fish related to the minnows and carps rather than the true loaches. Among the 'sharks', the ones that have been referred to the genus Labeo are probably the best know, though several of the most famous, including the Red-Tail Black Shark, have now been moved off into more narrowly defined genera (in this case, Epalzeorhynchos bicolor).

Nonetheless, some true Labeo are kept by aquarists, including Labeo cyclorhynchus, an African species known as the Harlequin Shark on account of the beautiful orange, red, yellow and black speckles that cover its body and fins when young. These colours are presumably camouflage of some sort, given it naturally inhabits tannin-stained rainforest rivers where this sort of mottled colouration would help it hide away among sunken wood and aquatic vegetation. Colouration does darken with age though, though rows of small red or orange spots will still be clearly visible along their flanks. Adult length is around 15 cm, though these are stocky fish that need a deep tank with plenty of swimming space.

Like most of the other 'sharks', the Harlequin Shark is territorial and tends to become more aggressive with age. Dissimilar schooling fish will usually be ignored, and things like Nurse Tetras, Congo Tetras or Africa Red-Eye Tetras could be used to help create the right sort of biotope community. But bottom dwelling fish are going to be viewed with more suspicion. The smaller bichirs for example are too slow moving to avoid trouble, and while Synodontis can hold their own given sufficient hiding places, this will only work if the tank is big enough for both catfish and 'shark' to avoid each other most of the time. Harlequin Sharks are omnivores, algae wafers as a staple, and small invertebrates such as bloodworms and brine shrimps as periodic treats.

Panda Loach, Protomyzon pachychilus

This is another fish that isn't really a true loach despite its name, but a member of the so-called Hillstream Loach family, or Gastromyzontidae, which as their name suggests, come from upland streams where the water is cool, fast-flowing, and very well oxygenated. While not well suited to generic community tanks, Hillstream Loaches are small, peaceful, and often very pretty, so they have become popular among those aquarists happy to set aside a tank to their specific needs.

The Panda Loach gets its name from the thick black and white bands seen on juveniles. Adults have a more complex mixture of black blotches, metallic grey mottling, and an off-white background colour. Maximum length is around 5 cm. Although mildly territorial, these loaches work nicely in groups, and are certainly fun to watch as they nudge each other away from their chosen feeding spot.

Water quality is paramount when keeping these loaches successfully. Water chemistry is less critical; we recommend 2-15 degrees dH, pH 6.5-7.5, but the main thing is that the water is not too warm (22-25C) but with a brisk current and plenty of oxygen. Feeding is not too difficult, with a good quality algae wafer making the best staple, augmented periodically with occasional offerings of small invertebrates such as brine shrimps. They are classic 'aufwuchs' feeders though, so bright light to encourage the growth of green algae will go a long way towards ensuring continued good health.

Chocolate Whiptail Catfish, Hemiloricaria lanceolata

Whiptails are among the most underrated catfish in the hobby, being remarkably hardy despite their delicate appearance. While most species are nondescript in colouration, this species is has a striking chocolate brown stripe running along each flank. There's a good deal of variation within the species, ranging from ones with an obvious mottled tan background to the stripes all the way through to some that are almost entirely chocolate brown. Combined with its slender shape and large dorsal and tail fins, the result is a very attractive and interesting addition to most community tanks. Maximum length is around 10 cm.

Like other whiptails the Chocolate Whiptail Catfish is an adaptable omnivore with a preference for small invertebrates that it can sift out of a sandy substrate. Although members of the suckermouth catfish family, they do not eat much algae, and should be maintained in much the same way as Corydoras. Indeed, small groups of whiptails make a nice alternative to Corydoras, getting along well with small tetras and other inoffensive community species. Whiptails are adaptable with regard to water chemistry and temperature, but as with all fish they appreciate good water quality.

Giant Oto, Hypoptopoma gulare

Compared to the Common Otos, Otocinclus spp., these catfish are similar in shape but much bigger, around 10 cm long when fully grown. They occupy much the same ecological niche in the wild, consuming green algae and tiny invertebrates from rocks and sunken wood, but in the aquarium have proven to be a lot easier to keep. For a start they're not such fussy feeders as true Otocinclus, happily consuming algae wafers, frozen brine shrimp, bloodworms, and other small foods. They are also much less nervous and even a little territorial towards their own kind, and unless the tank is big enough for a reasonably large group, five or more specimens, this species is best kept singly.

As such, these are interesting alternatives to Ancistrus, performing the same sort of algae-eating service while being a bit more active and entertaining to watch. They are fairly adaptable with regard to water chemistry provided very hard water is avoided, but a bit of current and a decent level of oxygen should both be provided. They're good companions for tetras, barbs, danios and other active community fish that require similar conditions.