Pictus catfish

Water parameters

Tolerated range for this species. Aim for the middle of each band rather than the extremes.

Tank and habitat

Substrate: sand.

Behavior

Plant interaction: plant safe.

Typically wild-caught; acclimate slowly.

Feeding

Unfussy and food-motivated. Sinking pellets and wafers form the staple diet. Frozen bloodworm, brine shrimp, and mysis shrimp are accepted eagerly. Live blackworms trigger a strong feeding response and are worth offering occasionally. The long barbels are taste and touch organs; the fish explores the entire substrate surface methodically at feeding time, vacuuming up anything edible. Despite being labeled nocturnal, most captive pictus learn to feed in daylight within a few weeks of settling in. Feed once daily, slightly after lights-on or just before lights-out. Overfeeding is easy because they eat fast and beg convincingly. Sand substrate is preferred because it protects the barbels; coarse gravel abrades them over time and can lead to bacterial infection at the base.

Nocturnal feeder; drop food after lights out.

Compatibility

• Peaceful toward same-sized fish but a capable predator of small species. That mouth is wider than it looks. Neons, ember tetras, chili rasboras, and any shrimp are food items. Minimum tankmate size: 4 cm body length, which rules out most nano fish.
• Works well with medium community species: larger tetras (black skirt, congo), rainbowfish, barbs, and other catfish. Corydoras make natural companions since they share substrate level but are too stocky to be swallowed.
• Sharp pectoral fin spines that lock into an erect position when the fish is startled or netted. The spines are mildly venomous. A sting feels like a wasp sting and throbs for a few hours. Never net a pictus with a soft mesh net; the spines tangle and you'll injure the fish trying to free it. Always use a rigid container or cup to move them.
• Social. Single specimens hide constantly and feed poorly. Groups of 4-6 settle in faster, show more natural behavior, and come out of hiding during the day. Two is worse than one because they compete for the single best hiding spot.

Origin and habitat

Pimelodus pictus, the pictus catfish, is an active, spotted catfish from the Amazon and Orinoco basins of northern South America. Steindachner described it in 1876 from the Yavari on the Peru-Brazil border, and the species name pictus, painted, refers to the pattern of black spots on a silver body. It belongs to the long-whiskered catfish family Pimelodidae, and its barbels are strikingly long, reaching back toward the tail. Two regional forms reach the trade: Colombian fish carry fine peppered spots, while Peruvian fish have larger blotches. Like other pimelodids it is scaleless, its body protected by a mucus coating rather than scales, which leaves it prone to ich and sensitive to many medications. It also carries sharp, mildly venomous spines on the dorsal and pectoral fins that lock outward when the fish is alarmed; these tangle hopelessly in soft nets and can pierce a bag, so the fish should be moved in a rigid container, and a jab feels like a wasp sting. It grows to around 11 to 13 cm and is a restless, shoaling swimmer that needs a long tank.

Breeding

Pictus catfish are not bred in home aquariums. They are egg-layers in the wild, but the triggers, presumably tied to seasonal floods and migration, cannot be reproduced in a tank, and the sexes are hard to tell apart beyond a gravid female looking a little fuller. The trade runs almost entirely on wild-caught fish from the Amazon and Orinoco; some hormone-induced commercial breeding has been reported in Southeast Asia, but no captive-bred stock has reached the general hobby.

Common problems

Two things catch new keepers out. The first is the spines: when stressed or handled the fish locks its serrated, mildly venomous pectoral and dorsal spines outward, so it tangles in mesh nets, can puncture transport bags, and can sting a hand, and the answer is always to move it in a container rather than a net. The second is the barbels, which the fish navigates and hunts by; coarse gravel wears them down over time and invites infection at the base, so fine sand is the right substrate. Being scaleless, the pictus is quick to catch ich and is sensitive to medication, so treatments should be given at reduced doses. New wild-caught fish often arrive thin and stressed and benefit from quarantine and heavy feeding. Many keepers also underestimate the tank: these are tireless night swimmers that cruise the whole length of the tank, so a long aquarium is essential.

Bioload

Further reading

• How to cycle a fish tank
• Stocking ideas by tank size