Description

The assassin snail is a snail that eats snails. A conical shell with yellow and brown bands, about 2.5 cm long, and a proboscis it pushes in through the opening of its prey's shell. It is sold as biological control for bladder, ramshorn or Malaysian trumpet snail outbreaks, and it works: a small population clears a tank of snails within a few months.

It is worth thinking about what happens next. Once the snails are gone it eats sinking food, meat and leftovers, and survives well. It can also attack snails you want to keep if they are its size or smaller, such as young apple snails.

It breeds in fresh water, but slowly: it lays eggs one at a time and never becomes a pest.


Scientific name
Anentome helena
Difficulty
Easy

Habitat

It lives in rivers and lakes of Southeast Asia, from Thailand to Indonesia, buried in sand or mud and emerging to hunt. In the aquarium it appreciates a sandy substrate to dig into.

As a predator of snails it must never be released into the wild: where it has been introduced it threatens native snails.

🌊 Water parameters

pH
7 - 8
GH
6 - 15
Temperature
22 - 28 °C
Current
Low or moderate

What about your tank?

Enter your tank's values to see only the compatible species that fit them. Litres apply to fish.

Compatible fish

General guidance based on water parameters, behaviour and known exceptions; always review the individual animals' and aquarium's specific needs.

Ancistrus temminckii

Ancistrus

Image byis licensed under CC BY 3.0 (resized)

They share water: pH 7–7.5 and 22–27 °C.

They share water: pH 7–7.5 and 24–28 °C.

Melanotaenia boesemani in Ouwehands Dierenpark

Arcoíris de Boeseman

Image byFakirNLis licensed under CC BY-SA 4.0 (resized)

They share water: pH 7–8 and 26–28 °C.

They share water: pH 7–7.5 and 22–27 °C.

Rohanella titteya

Barbo cereza

Image bybrian.gratwickeis licensed under CC BY 2.0 (resized)

They share water: pH 7–7.5 and 22–27 °C.

They share water: pH 7–7.5 and 22–27 °C.

betta

Betta

Image byDaniella Vereekis licensed under CC BY 2.0 (resized)

They share water: pH 7–7.5 and 24–28 °C.

Hemigrammus Rhodostomus

Borrachito

Image byBernat Arlandisis licensed under CC BY-SA 2.0 (resized)

They share water: pH 7 and 22–28 °C. They only meet at the very edge, so the tank has to hold that value.

They share water: pH 7–7.5 and 25–28 °C.

Crossocheilus siamensis by Ark

Comedor de algas siamés

Image byArkis licensed under CC BY 3.0 (resized)

They share water: pH 7–8 and 24–26 °C.

Corydoras aeneus

Corydoras aeneus

Image byAndrew Kelleris licensed under CC0 (resized)

They share water: pH 7–8 and 22–26 °C.

Corydoras panda

Corydoras panda

Image byDornenwolfis licensed under CC BY 2.0 (resized)

They share water: pH 7–7.5 and 22–25 °C.

Corydoras Sterbai

Corydoras sterbai

Image byMatthew Mannellis licensed under CC0 (resized)

They share water: pH 7–7.5 and 24–28 °C.

Danio rerio

Danio rerio

Image byMarrabbio2is licensed under CC0 (resized)

They share water: pH 7–7.5 and 22–24 °C.

Brown Discus Symphysodon aequifasciatus

Disco

Image byBrian Gratwickeis licensed under CC BY 2.0 (resized)

They share water: pH 7 and 27–28 °C. They only meet at the very edge, so the tank has to hold that value.

 Pterophyllum scalare

Escalar

Image byKareljis licensed under CC0 (resized)

They share water: pH 7–7.5 and 24–28 °C.

The guppy

Guppy

Image byCarlos Eduardo Joosis licensed under CC BY 2.0 (resized)

They share water: pH 7–8 and 22–28 °C.

Endler Guppy 'Yellow Top Sword'

Guppy Endler

Image byDornenwolfis licensed under CC BY 2.0 (resized)

They share water: pH 7–8 and 22–28 °C.

Thrichogaster lalius

Gurami Enano

Image byBernat Arlandisis licensed under CC BY-SA 2.0 (resized)

They share water: pH 7–7.5 and 25–28 °C.

They share water: pH 7–8 and 22–28 °C.

Honey gourami red variant

Gurami miel

Image byEevaya is licensed under CC BY-SA 4.0 (resized)

They share water: pH 7–7.5 and 22–28 °C.

Gurami perla

Gurami perla

Image byChmee2is licensed under CC BY 3.0 (resized)

They share water: pH 7–7.5 and 24–28 °C.

Pelvicachromis pulcher (male)

Kribensis

Image byTino Straussis licensed under CC BY-SA 3.0 (resized)

They share water: pH 7–7.5 and 24–27 °C.

Kuhli loach in aquarium

Locha kuhli

Image byIidkkis licensed under CC BY-SA 4.0 (resized)

They share water: pH 7 and 24–28 °C. They only meet at the very edge, so the tank has to hold that value.

Poecilia sphenops wild form

Molly

Image byDnoerholmis licensed under CC BY-SA 4.0 (resized)

They share water: pH 7.5–8 and 24–28 °C. They only meet at the very edge, so the tank has to hold that value.

They share water: pH 7.5–8 and 24–28 °C. They only meet at the very edge, so the tank has to hold that value.

Paracheirodon innesi

Neón

Image byGunnar Ries zwois licensed under CC BY-SA 2.0 (resized)

They share water: pH 7 and 22–26 °C. They only meet at the very edge, so the tank has to hold that value.

Poropanchax normani

Ojo de Lámpara de Norman

Image byCisamarcis licensed under CC BY-SA 3.0 (resized)

They share water: pH 7–7.2 and 22–26 °C.

Otocinclus

Otocinclus

Image byNico Hernandezis licensed under CC BY 4.0 (resized)

They share water: pH 7–7.5 and 22–26 °C.

They share water: pH 7–8 and 22 °C. They only meet at the very edge, so the tank has to hold that value.

Carassius auratus auratus (goldfish)

Pez dorado

Image byJames St. Johnis licensed under CC BY 2.0 (resized)

They share water: pH 7–8 and 22–24 °C.

Two Xiphophorus maculatus in aquarium

Platy

Image byCarlosaris licensed under CC BY-SA 3.0 (resized)

They share water: pH 7–8 and 22–27 °C.

Mikrogeophagus ramirezi imported from Columbia

Ramirezi

Image byFrank M Grecois licensed under CC BY 3.0 (resized)

They share water: pH 7 and 26–28 °C. They only meet at the very edge, so the tank has to hold that value.

Trigonostigma heteromorpha

Rasbora Arlequín

Image byStefan Maurer is licensed under CC BY 2.0 (resized)

They share water: pH 7 and 22–26 °C. They only meet at the very edge, so the tank has to hold that value.

Danio margaritatus

Rasbora galaxy

Image byBread962is licensed under CC BY 4.0 (resized)

They share water: pH 7–7.5 and 22–26 °C.

Tetra ember

Tetra ember

Image byUsienis licensed under CC BY 3.0 (resized)

They share water: pH 7 and 23–28 °C. They only meet at the very edge, so the tank has to hold that value.

Hyphessobrycon pulchripinnis

Tetra limón

Image byWaugsbergis licensed under CC BY 2.5 (resized)

They share water: pH 7–7.5 and 23–28 °C.

Tetra negro

Tetra negro

Image bySerentier is licensed under CC0 (resized)

They share water: pH 7–7.5 and 22–26 °C.

black neon tetra

Tetra neón negro

Image byBrian Gratwickeis licensed under CC BY 2.0 (resized)

They share water: pH 7–7.5 and 23–27 °C.

Hyphessobrycon eques

Tetra serpae

Image byDouglas Lopesis licensed under CC BY 4.0 (resized)

They share water: pH 7–7.5 and 22–27 °C.

Xiphophorus hellerii red male

Xipho

Image byWojciech J. Płuciennikis licensed under CC BY-SA 4.0 (resized)

They share water: pH 7–8 and 22–28 °C.

Compatible invertebrates

General guidance based on water parameters, behaviour and known exceptions; always review the individual animals' and aquarium's specific needs.

Ampularia

Ampularia

Image byÁngel Ramosis licensed under CC BY-SA 4.0 (resized)

They share water: pH 7–8 and 22–28 °C.

Cangrejo Thai micro
AI: ChatGPT

Cangrejo Thai micro

Image byHectoris licensed under CC BY 4.0 (resized)

They share water: pH 7–7.5 and 22–27 °C.

Cangrejo enano CPO

Cangrejo enano CPO

Image byVeitwis licensed under CC BY-SA 3.0 (resized)

They share water: pH 7–8 and 22–25 °C.

Cangrejo pantera

Cangrejo pantera

Image byLaesaMajestasis licensed under CC BY-SA 4.0 (resized)

They share water: pH 7.5–8 and 24–28 °C.

Cangrejo vampiro

Cangrejo vampiro

Image byAverageWalrusis licensed under CC BY-SA 4.0 (resized)

They share water: pH 7–8 and 22–28 °C.

Tylomelania zemis
AI: ChatGPT

Caracol conejo

Image byHectoris licensed under CC BY 4.0 (resized)

They share water: pH 7.5–8 and 26–28 °C.

Caracol cuerno
AI: ChatGPT

Caracol cuerno

Image byHectoris licensed under CC BY 4.0 (resized)

They share water: pH 7–8 and 22–28 °C.

They share water: pH 7–7.5 and 22–26 °C.

Gamba Amano

Gamba Amano

Image bySky99is licensed under CC BY-SA 4.0 (resized)

They share water: pH 7–7.5 and 22–27 °C.

They share water: pH 7.5–8 and 27–28 °C.

Neocaridina davidi
AI: ChatGPT

Neocaridina Black Rose

Image byHectoris licensed under CC BY 4.0 (resized)

They share water: pH 7–7.5 and 22–26 °C.

Neocaridina Blue Dream

Neocaridina Blue Dream

Image byRoth 1312is licensed under CC BY 4.0 (resized)

They share water: pH 7–7.5 and 22–26 °C.

Neocaridina Green Jade
AI: ChatGPT

Neocaridina Green Jade

Image byHectoris licensed under CC BY 4.0 (resized)

They share water: pH 7–7.5 and 22–26 °C.

Neocaridina Orange Sakura

Neocaridina Orange Sakura

Image byDack9is licensed under CC BY 4.0 (resized)

They share water: pH 7–7.5 and 22–26 °C.

They share water: pH 7–7.5 and 22–26 °C.

They share water: pH 7–7.5 and 22–26 °C.

Neritina cebra

Neritina cebra

Image byEvan Baldonadois licensed under CC BY 4.0 (resized)

They share water: pH 7–8 and 22–28 °C.

Neritina pulligera
AI: ChatGPT

Neritina pulligera

Image byHectoris licensed under CC BY 4.0 (resized)

They share water: pH 7–8 and 22–28 °C.

Sources

  • GBIF
    GBIF Secretariat (2026). GBIF Backbone Taxonomy. Checklist dataset. https://doi.org/10.15468/39omei. Consultado vía GBIF.org, 2026-08. Anentome helena.

Taxonomy verified as ACCEPTED unless stated otherwise.

The care values (pH, temperature and hardness) have no citable source: none of the accepted sources publishes invertebrate profiles. Seriously Fish has none and PlanetCatfish does not respond. A source for invertebrates is still to be agreed.