Clown Loach (Chromobotia macracanthus)

Chromobotia macracanthus, the Clown Loach, is one of the most beloved and widely recognised freshwater aquarium fish. Its vivid colouration — a brilliant orange-red body crossed by three bold black vertical bands — combined with its comical, social behaviour and apparent 'personality' has made it a centrepiece fish of the community aquarium hobby for decades.

Native to Sumatra and Borneo in Indonesia, the Clown Loach inhabits large rivers, flooded forests, and tributaries in its native range. It is a migratory species — adults undertake seasonal migrations to breeding grounds during the monsoon season, a behaviour impossible to replicate in captivity, which is why successful breeding in aquariums is extremely rare.

One of the most critical aspects of Clown Loach care is understanding their eventual size: adults reach 25–30 cm in nature (and 20–25 cm in large aquariums) and are extremely long-lived — well-cared-for specimens regularly exceed 20 years of age. Many aquarists purchase small Clown Loaches as juveniles (4–5 cm) without appreciating that they will eventually require aquariums of 400–600 litres or more.

Clown Loaches are obligately social — solitary or pairs exhibit severe stress, hiding constantly, refusing food, and developing health problems. Groups of five or more are the minimum, with larger groups of 8–10+ producing the most natural, active, and visible behaviour. They are famous for 'playing dead' — lying on their sides apparently motionless — which is entirely normal behaviour that frequently alarms new keepers.

Tank Setup: Juvenile Clown Loaches can be kept in 120-litre tanks temporarily, but adult fish require 400–600+ litres. Provide a sandy or smooth substrate, driftwood, caves (PVC tubes are favourites), moderate planting, and very good filtration. Strong oxygenation is important. A tight lid — they can jump.

Water Parameters: Temperature 25–30°C; pH 6.0–7.5; GH 5–12 °dH; KH 2–8 °dH. Prefers soft to moderately hard, slightly acidic to neutral water. Avoid very hard, alkaline conditions.

Feeding: Omnivore. Feed sinking pellets, wafers, frozen bloodworm, brine shrimp, Daphnia, Tubifex, and blanched vegetables. Clown Loaches are enthusiastic snail predators — they will consume pest snails (Ramshorn, Malaysian Trumpet, Bladder snails) in planted tanks. Feed in the evening.

Tank Mates: Generally peaceful and compatible with most medium to large community fish: tetras, barbs, rainbowfish, corydoras, medium cichlids. Avoid very small fish that may be accidentally eaten as adults grow large.

Behaviour: Social and interactive. Plays dead — lying on its side — which is entirely normal and not cause for alarm. Makes clicking sounds when excited or feeding. Larger groups are more active and less shy.

Health: Highly susceptible to ich (white spot) — particularly sensitive as their scales are small and body covering minimal. Treat at first signs with raised temperature and medication. Sensitive to many medications including formalin-based treatments. Clown Loaches are ich magnets — pristine water reduces risk significantly.