Black Devil Snail
Faunus ater
- Care level
- Intermediate
- Adult size
- 6–9 cm
- Minimum tank
- 60 litres
- Temperature
- 22–28 °C
Species profile
Assassin Snail
Anentome helena
Common names: Assassin Snail, Bumblebee Snail, Killer Snail
Recognized speciesAssassin Snails
Adult size
Up to 3 cm
Typical adult length 1.5–3 cm.
Up to 3 cm
Countries of origin
Good fit for your tank?
Good fit for
- Mature planted aquarium setups
- Beginner shrimp keepers
- Peaceful nano aquariums
Think carefully if
- The tank is newly cycled
- Water conditions change frequently
A small Southeast Asian predatory snail that burrows into fine substrate and feeds largely on other snails. It requires mineral-rich freshwater and regular meaty food when prey is scarce.
Appearance and Identification
A small conical snail with alternating yellow, tan, and dark brown spiral bands, a grey mottled body, and a long extensible siphon.
The banded conical shell, operculum, long siphon, and predatory behaviour distinguish it from common algae-grazing snails. Clea helena is a synonym rather than a different aquarium species.
Sexes are separate but cannot be reliably distinguished from shell colour or shape. Females may be slightly larger, and sex is most reliably inferred from repeated mating or egg laying.
Tank Requirements
- Suggested filter
- About 40–60 litres an hour
- Suggested heater
- About 25–50 W for this tank
- Minimum tank volume
- 20 litres
- Minimum tank length
- 30 cm
- Minimum group size
- 1
- Recommended group size
- 5
- Activity level
- Moderate
- Flow preference
- Low
- Planting preference
- Moderately planted
- Hiding places
- Yes
- Lid recommended
- Yes
- Jumping risk
- Low
Use fine sand or smooth fine gravel for natural burrowing. Provide hard water, stable filtration, open feeding areas, and a secure lid. A group is useful for breeding because external sexing is unreliable.
Behaviour and Tankmates
A bottom-dwelling ambush predator and scavenger that often remains buried with only its siphon exposed.
Can live singly. A group improves the chance of containing both sexes but increases demand for animal-based food.
Not territorial, although several snails may converge on the same prey or food item.
Generally compatible with peaceful fish and robust adult shrimp, but it will attack many other snails and may consume very small, weak, or freshly moulted invertebrates. Avoid keeping it with valued ornamental snails.
Water Parameters
Neutral to alkaline, moderately hard water protects the shell. Very soft acidic water can cause erosion and poor growth.
Parameter caveat
Avoid copper-based medication and sudden mineral changes. Predatory fish and snail-eating loaches can injure or consume the snail.
Feeding
- Diet types
- Carnivore, Predator, Scavenger
- Preferred foods
- Small pest snailsNatural prey, but the aquarium should not depend on uncontrolled prey breeding.
- Frozen bloodworm or blackwormPlace small portions close to the substrate.
- High-protein sinking pelletEssential when live snail prey is unavailable.
- Fresh carrion from safe aquatic foodsUse very small portions and remove remains promptly.
A carnivorous predator and scavenger specialising in other snails but also accepting worms, carrion, and protein-rich prepared foods.
Continue feeding after nuisance snails decline. Starvation is not an acceptable population-control method.
Breeding
- Breeding type
- Egg Layer, Underwater Egg Clutch
- Breeding difficulty
- Moderate
- Breeding temperature
- 25 °C
- Breeding pH
- 7.5
- Brood or egg count
- Single eggs deposited separately in individual capsules.
- Incubation
- 42 days
- Parental care
- None
- Baby foods
- Very small snailsNatural prey for growing juveniles once they begin active hunting.
- Fine high-protein sinking foodPlace tiny portions near the substrate.
- Microworms or finely chopped frozen wormsUse sparingly as supplementary animal food.
The species has separate sexes. After mating, females place individual square or oval egg capsules on glass, wood, rock, or plant surfaces. Development is slow, and juveniles often remain hidden in the substrate.
Habitat and Origin
- Geographic origin
- Asia, Cambodia, Indonesia, Laos, Malaysia, Southeast Asia, Thailand, Vietnam
- Natural habitat
- Freshwater River, Freshwater Stream, Sand/Mud Substrate
- Aquarium contexts
- Freshwater Aquarium, Nano Aquarium, Planted Aquarium, Snail Tank
- Audience level
- Beginner
Classification
- Profile type
- Recognized species
- Genus
- Anentome
- Family
- Nassariidae
- Species group
- Assassin Snails, Invertebrates, Snails
- Previous scientific names
- Clea helena, Historic combination still common in aquarium literature; currently accepted as Anentome helena.
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- Adult size
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- Minimum tank
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- Temperature
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