Black Helmet Snail

Neritina pulligera knorii

Neritina pulligera knorii (“Black Helmet”, “Casque”) is a small freshwater snail from the Neritidae family with a smooth, dome-shaped shell that is almost uniformly black with an orange band along the inner edge of the aperture. Peaceful and undemanding cleaner, feeding on algae encrustations; grows to about 2 cm. It inhabits slow-moving freshwater rivers and streams in Southeast Asia and Indo-Pacific islands. In the aquarium, it needs a lid (prone to escapes), does not tolerate copper-containing medications; it does not breed in freshwater as larvae require brackish water.

Minimum aquarium volumefrom 20 Lallowed from 15 L

Adult size1–2 cm

Water temperature22–28 °Callowed 18–30 °C

pH7–8.5allowed 6.5–8.5

General hardness8–15 °dGHallowed 5–25 °dGH

Population growth riskLow

Overview

ProfileGastropod mollusk

Aquarium rolesDecorative, Algae grazer, Biofilm grazer

Adult size1–2 cm

Social modelSolitary

Minimum addition quantity1

DietGrazer, Herbivore, Detritivore

Before you buy

Starvation risk: The risk of starvation is high. The snail feeds almost exclusively on algae encrustations and biofilm and, unlike many "cleaners," rarely eats fish leftovers or common invertebrate foods. In a clean aquarium without sufficient algae and without supplemental feeding, it may die from exhaustion. It is essential to keep it only in an established aquarium with encrustations and/or additional feeding of blanched vegetables and spirulina tablets.

Responsible disposal: Do not release the snail, its eggs, or offspring into natural water bodies. Neritina pulligera and related species (including Neritina knorri) are introduced species in some regions and can disrupt local ecosystems. If necessary, dispose of the animal by passing it to other aquarists, a pet store, or a veterinary clinic for humane disposal. Do not drain the aquarium contents into natural water bodies or the sewage system.

Escape and lid requirements: Neritina are known escape artists: they actively crawl on tank walls and can leave the aquarium without a lid, especially when food is scarce or water parameters deteriorate. A tightly fitting lid or cover glass is mandatory. All gaps (under filter, heater, in corners) must be sealed. Out of water, the snail can survive for several hours but then dies from desiccation. When kept in an open aquarium, reduce water level by a few centimeters.

Black Helmet Snail

Overview

Care

Compatibility