Assassin Snail
Anentome helena · family Nassariidae
Parameters
- Temperature
- 20–28 °C
- pH
- 7–8
- Hardness
- 8–20 °dGH
- Tank volume
- from 20 L
- Maximum size
- up to 2 cm
- Group size
- min 2, ideal 5
- Temperament
- Predator
- Difficulty
- Beginner
- Lifespan
- 1–2 years
Pros and cons
- Natural control of 'snail outbreaks' — eats ramshorns and trumpet snails
- Breeds very slowly — won't replace one problem with another
- Decorative yellow-and-black striped shell
- Leaves fish and adult shrimp alone
- Needs meaty food (bloodworm) after the prey snails are gone
- May hunt juveniles of expensive shrimp
- Won't crush a large ramshorn population fast (3–5 assassins per 50 L)
- Sensitive to low pH (shell erodes)
Description
A predatory snail with a conical striped shell. Used to control populations of other snails (ramshorns, MTS). Reproduces slowly — won't replace the original problem.
FAQ
- How many assassin snails do I need to clear ramshorns from a 100 L tank?
- 5–8 individuals. Within 2–3 months the ramshorn population drops to a negligible level. After that, the assassins need supplementary feeding.
AuthorGoldie Editorial
Goldie editorial team
Practising aquarists with a combined 30+ years of experience · Biologists and editors, fact-checking against FishBase and Seriously Fish · Every piece is reviewed by a qualified ichthyologist before publication
Reviewed byGoldie Science Board
Scientific board — ichthyologists and veterinarians
Ichthyologists and veterinarians with university degrees · Reference FishBase, Seriously Fish and peer-reviewed literature · Sign every reviewed article with their credentials shown
Sources
- Wikipedia: Anentome helena · Wikipedia · 2026-05-22