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

Native to the Amazon and Orinoco river basins in Colombia, Venezuela, Peru, and Brazil. Tends to be found in shallow, flowing waters over sandy or muddy substrates, including major river channels and their tributaries; often encountered in shoals. Described by Steindachner in 1876. The species name pictus is Latin for "painted," referring to the spotted pattern. Silver body with black spots and stripes; barbels are extremely long and can extend to the caudal fin. Two geographic variants are imported: Colombian fish have tiny peppered spots, while Peruvian fish have much larger spots on the body. Scaleless, which makes them highly susceptible to diseases like whitespot and sensitive to many common medications. Sharp spines on dorsal and pectoral fins can puncture plastic bags during shipping and catch in nets; the spines may be mildly venomous. Use a container rather than a net to move them. Grows to about 11–12 cm total length. Average lifespan in captivity is 4-8 years, though one documented case reached 18 years. Active swimmers that need space; a minimum aquarium length of 120 cm is the usual recommendation. Opportunistic predators that will eat anything fitting in their mouth. Wild-caught fish can arrive in poor condition from a combination of malnutrition and oxygen deprivation.

Breeding

Not bred in home aquariums. Every pictus catfish in the trade is wild-caught from river systems in the Amazon and Orinoco basins. The specific triggers for spawning are unknown, but likely involve seasonal flood cycles, large migrations, and environmental cues that can't be replicated in a glass box. Sexing is unreliable; gravid females may appear slightly rounder when full of eggs, but that's about it. Attempts at hormone-induced spawning in commercial facilities have reportedly occurred in Southeast Asia but details are scarce and no captive-bred stock has reached the general hobby market.

Common problems

The pectoral spine issue deserves emphasis because it catches every new keeper off guard. When stressed or handled, pictus catfish flare and lock their pectoral spines outward. These spines are serrated and mildly venomous. Consequences: they get tangled in nets (use a container, always), they can puncture transport bags (double-bag with a rigid inner container), and they can sting your hand if you're reaching into the tank. The sting isn't dangerous but it hurts. Barbel damage from rough substrates is the other common problem. Gravel substrates wear down the barbels over months; shortened or eroded barbels impair the fish's ability to find food because they navigate and hunt almost entirely by touch. Sand substrate prevents this. Ich is common in newly imported wild-caught specimens. Pictus catfish are scale-covered (despite looking smooth), so standard ich treatment at half dose is safer than the full dose used for scaled fish. A lot of keepers underestimate tank size requirements. Pictus are restless swimmers that cruise the entire tank at night. A 120 cm tank is the minimum for a group, and even then they'll use every centimeter.

Bioload

Further reading

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