Purple Cobra Candiru (Cetopsis candiru)

Purple Cobra Candiru — Cetopsis candiru

River myth turned real predator

The Purple Cobra Candiru is one of the most intense oddball predators you can keep. Long, slender, and built like a living blade, this South American catfish carries a smoky violet-to-charcoal body that can shift in tone depending on mood and lighting. Its elongated head and sharp, fang-like teeth give it a cobra-like appearance — a look that earned it its name.

Native to Amazonian river systems, Cetopsis candiru is not a timid scavenger. Unlike parasitic candiru species people talk about in myths, this member of the whale catfish family is an active carnivorous predator. It patrols the lower water column with purpose, using speed and precision to strike at meaty foods. Feeding response is immediate and aggressive, often surprising keepers who underestimate its size.

Reaching 8–12 inches, the Purple Cobra Candiru is a compact but serious predator best suited for experienced aquarists who understand feeding management and tank mate selection.

Aquarium Setup

• Minimum Tank Size: 90–125 gallons

• Substrate: Sand or smooth gravel

• Flow: Moderate

• Décor: Driftwood structure with open swimming lanes

• Lighting: Dim to moderate

• Cover: Secure lid recommended

• Filtration: Strong biological filtration required

Tank Mates

Best kept with larger, robust species:

• Large cichlids

• Datnoids

• Medium to large catfish

• Other confident predator fish

Avoid small fish — they will be eaten. Avoid very slow or delicate species.

Water Parameters

• Temperature: 75–82°F (24–28°C)

• pH: 6.0–7.5

• Hardness: Soft to medium

• Water Quality: Clean and stable conditions essential

Diet

Strict carnivore:

• Fish fillet

• Shrimp and prawn

• Worms

• High-protein sinking pellets (once trained)