Black devil snail (Faunus ater) care guide

Group
Snails
Other names
Black faunus snail, Black devil, Faunus snail
Family
Pachychilidae
Origin
Indo-West Pacific coasts and rivers, including Malaysia, Singapore and the Philippines, in slightly brackish and fresh water
Water
freshwater
Maximum size
9 cm
Temperature
22–28°C
pH
7–8.2
Hardness
8–15 dGH, 4–10 dKH
Minimum tank
60 litres
Care level
beginner
Lifespan
3–5 years

Care

The black devil snail is the only living member of the genus Faunus, a large, slender snail with a tall spire of about 20 whorls. The shell is usually 5–6 cm tall but can reach 9 cm, covered in a dark brown to black skin, with a white mouth. Older snails often have worn tips. It is the only member of its family that lives in brackish water, though it is also found in fresh water, sometimes in very dense groups. Set-up: a tank of 60 litres or more with a sandy or fine gravel bottom, rocks and wood. It does well in hard, alkaline fresh water and also in slightly brackish water. Temperature and water figures here are general guidance rather than from a source. Role in the tank: a grazer that cleans algae and biofilm from surfaces and sifts through the substrate for detritus and leftover food. It is generally considered plant-safe. It is a long-lived, slow-growing snail and an eye-catching alternative to rabbit snails. Copper: copper-based medicines and some plant fertilisers are toxic to shrimp, snails and most other invertebrates. Never treat a tank holding them with copper, check the label of any fertiliser or medicine, and keep nets and buckets used for copper-treated tanks separate. Sources: Wikipedia (en.wikipedia.org/wiki/Faunusater). Checked October 2026.

Diet

Grazes algae, biofilm and detritus. Supplement with sinking algae wafers, blanched vegetables and calcium-rich foods, especially in a clean tank.

Breeding

It lays eggs and probably has free-swimming larvae that need brackish water, so it is not known to breed in freshwater aquariums. Nearly all stock is wild-caught.

Compatibility and tank mates

Peaceful and safe with fish, shrimp, other snails and plants. Avoid assassin snails, puffers and snail-eating loaches.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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