Fish
Cascarudo
Callichthys callichthys
Origin: The cascarudo is widespread in South America — from the Orinoco and Amazon basins to the Río de la Plata. It inhabits slow rivers, ditches, swamps, and temporary pools with soft bottoms, often with low oxygen.
Also known as: Mailed catfish, Callichthys callichthys
Fact sheet
- Size
- 20 cm
- Lifespan
- 10 years
- Minimum tank size
- 150 L
- Temperature
- 18–28 °C
- pH
- 5.8–7.5
- Hardness GH
- 2–20 °dH
- Temperament
- Peaceful
- Social behavior
- Schooling
- Group size
- 3+ individuals
- Swimming zone
- Bottom
- Diet
- Omnivore
- Jumps out
- Yes
- Eats plants
- No
Overview
The cascarudo is a large armoured catfish, a relative of the corydoras, with an elongated body encased in two rows of bony plates. It is a hardy, peaceable, long-lived fish that breathes atmospheric air and tolerates very poor conditions. It is crepuscular and nocturnal, hiding in cover by day. Its calm nature suits a community tank with not-too-small companions. Undemanding and good for anyone wanting a large peaceful catfish.
Appearance
The body is elongated and rounded, covered by two rows of overlapping bony plates, up to 18–20 cm long. Colour is brownish-grey or olive with a metallic sheen, paler below. The head is broad with two pairs of barbels. Breeding males have a thickened, reddening first pectoral-fin ray.
Care
A tank of at least 150 L with soft substrate, cover, and a tight lid — the catfish gulps air at the surface and can escape. Temperature 18–28 °C, pH 5.8–7.5, hardness GH 2–20. The species is very hardy but appreciates clean water with regular changes and calm flow.
Feeding
An omnivorous bottom catfish. It takes sinking tablets and pellets, live or frozen bloodworm, tubifex, and earthworms, plus vegetable supplements. It feeds more actively at dusk. Feed once a day, preferably in the evening.
Compatibility
Peaceful toward similarly sized fish. It mixes well with large tetras, barbs, rainbowfish, calm cichlids, and other catfish. Very small fish may be accidentally sucked in with food. It can be kept in a group.
Breeding
It breeds in the aquarium. The male builds a bubble-and-plant nest at the surface, where eggs are laid; he then guards the clutch. Trigger spawning with soft water and an imitated rainy season — cool water changes. The fry hatch in 3–5 days.
Fun facts
The cascarudo can crawl over land in damp conditions in search of new water, propping itself on its pectoral fins. Like the corydoras it breathes through the gut, gulping air. It is one of the hardiest aquarium catfish, surviving conditions lethal to most fish.