Buy Tropical Fish Online - Tropical Fish Shop -

Price Match Guarantee - ☆☆☆☆☆ 4.8 Star Review Rating

  • Source: Copyright

  • Source: Copyright

  • Source: Copyright

The Clown Loach

The Clown Loach (Botia macracanthus)

Order Cypriniformes, Family Cobitidae

Common names

Clown Loach, Tiger Loach


Cobitis macrancanthus


The clown loach is a very striking fish, being a bright orange ornamented with three wide black stripes (although slight variations in the normal stripes do occur). They are a distinctive shape, with an almost flat ventral surface and a high, arched back. The mouth faces downwards, showing the fish’s preference for bottom feeding. They are not small fish, growing up to a foot in length, although many aquarium specimens never reach more than half this size. The fish originally come from Borneo and Sumatra; those from Borneo tend to have a black area in the pelvic fins, while in Sumatran fish the fin is completely orange. A movable spine rests in a groove below the eye, which should be treated with caution when netting the fish.


The clown loach is relatively peaceful, but is nonetheless a large fish when full grown with a preference for live foods. To a foot long fish inch-long tetra look very like live foods, so care should be exercised in choosing tank mates. They will be happiest in small shoals, so unless you have a huge aquarium there is unlikely to be room for many tankmates once they reach maturity anyway, although juveniles will occasionally join up with other shoaling fish in the aquarium. Loaches are mainly nocturnal, but clown loaches are more active during the day than many of their relatives, and generally provide an active and interesting aquarium display throughout the day.

Aquarium requirements

Hailing from rivers in Sumatra and Borneo (although the fish has been introduced to Thailand) the clown loach requires temperatures erring on the hot side (up to 86F, with a minimum of 75F) and clean, soft water with regular water changes. The aquarium should be chosen bearing in mind that the fish have the potential to grow large; at least a metre long is required to house even a small group. As naturally nocturnal fish, they will appreciate décor for them to hide in and relatively dim light. Loaches are bottom feeders and will grub through the substrate searching for food; hard edged gravel may damage their soft skins and sensitive (although small) barbels, so a soft substrate is strongly recommended.

A high protein diet is required for these fish, with live foods being particularly relished. In the aquarium they will do a good job cleaning up all the delicious high-protein snails, but this is no excuse for keeping them hungry to make them work harder. They will also take flake or pellet food, and vegetable food occasionally, although the majority of the diet should be meat-based. Although they are primarily bottom feeders, the loaches are agile aquarium inhabitants, and are quite capable of meeting the food on the way down and feeding in midwater or even at the surface.


Although clown loaches have been bred in captivity, both naturally and by hormonal stimulation, spawning in the aquarium is rare. This is probably more attributable to the fact there are very few groups of mature, full-size loaches being kept – many appear as solitary specimens in community tanks, and never reach their full breeding size. Naturally the loaches breed in the high, fast flowing reaches of rivers at the onset of the rains. On hatching the young descend the rivers to the calmer lower reaches, where they are collected for the aquarium trade. Juveniles caught at this time at about one and a half centimetres are easy for the collectors to grow on to raise a higher profit – with good feeding they can double in size in a week. Spawning has been achieved in the aquarium. One description involved a group of four foot-long fish. The temperature was raised to 86F, the upper end of the range, and water changes were stopped. After twelve days of this treatment the loaches became very active and fed ravenously on whitebait. After a month the temperature was reduced back to 82F by topping up the tank and reducing the build-up of nitrates. After feeding the fish then paired, rising entwined to the surface making clicking sounds. Although no spawning occurred then, in the morning the tank sides, base and décor was scattered with small, golden eggs, which the parents were not averse to devouring. Around 450 fry resulted from this spawning, which were raised on a liquid fry food followed by crushed flake.

Diseases and disorders

The clown loach has an alarming habit, shared by other botias, of resting on its side, unmoving. Although this behaviour is guaranteed to make the new owner suffer anxiety fits several times a day, it is actually perfectly normal and the fish are not on the verge of death, as might be supposed. The loach’s main weak point is its sensitive skin; unprotected by scales or armour plating, it is not only prone to white spot, but very sensitive to many medications on the market. Before treating a clown loach aquarium with any chemical, it is necessary to carefully read the instructions to ensure that the treatment is suitable. They have little protection against aggressive fish, and tank mates, if desired, should be chosen to be not only of a similar size to the loaches, but of a peaceful disposition. Like many fish, the colours of the clown loach can adjust according slightly to the mood and situation of the fish, and individuals may appear paler, with the stripes even appearing grayish, on occasion. If this only occurs for short intervals it is little cause for worry, but if one fish is abnormally pale for long periods of time it will be necessary to find out and remove the cause of the stress, which may be a water problem or a result of bullying by other inmates.


These are active and interesting fish, who merit their common name of ‘clown loach’ by more than their bright livery, but also by their endearing activities. Small fish will fit in well into a community aquarium, but a group of full-sized fish will more than deserve their large tank space requirements by being both beautiful and attractive – and possibly even spawning!

This article has been provided by Kathy Jinkings and cannot be reproduced without her permission

Other fish articles:

Other fish articles you may be interested in are listed below, click an article for full details.