Assassin Snail
Anentome helena
Care at a glance
- Temperature
- 72–81°F (22–27°C)
- pH
- 6.5–8.0
- Adult size
- 1 in (2.5 cm)
- Minimum tank
- 5 gal (20 L)
- Temperament
- Mostly peaceful
- Social behavior
- Solitary
- Swim level
- Bottom
- Difficulty
- Easy
- Breeding
- Medium
- Rarity
- Common
- Origin
- Malaysia, Thailand, Indonesia
- Family
- Nassariidae
Overview
Keep them as solitary bottom dwellers or in small numbers; they don't need company. They are mostly peaceful toward adult fish and shrimp but will eat pest snails, which is the usual reason people buy them. Hold water at 22 to 27 C and pH between 6.5 and 8. Feed sinking protein foods like bloodworms or a meaty pellet if you run out of snails for them.
In the wild
Assassin snails come from rivers, streams, and lakes across Malaysia, Thailand, and Indonesia, where they burrow into sandy or muddy bottoms. Give them a soft sand substrate so they can dig the way they do in the wild. A tank of 20 liters or more works, and they'll spend most of their time on or just under the bottom.
Good to know
This is a freshwater snail in the family Nassariidae, most of which are saltwater. It tops out around 2.5 cm with a cone-shaped shell banded in brown and yellow. It is a carnivore that hunts other snails and scavenges meaty leftovers. Wild populations are stable.
Did you know
They hunt by smell and use a drill-like radula to bore into a prey snail's shell, then reach in to feed. They will also work in pairs or groups to overpower a snail bigger than themselves.
Where to buy
Some links may not be the exact species or variety.
- Aquatic Arts Freshwater fish, shrimp and snails with an arrive-alive guarantee
- Flip Aquatics Quarantined shrimp, snails and nano fish
- LiveAquaria Freshwater and saltwater fish, inverts and corals
- Imperial Tropicals Freshwater fish and inverts bred at a Florida hatchery
- Dan's Fish Freshwater fish, shrimp and snails with a live arrival guarantee
- The Wet Spot Tropical Fish Large freshwater selection from a longtime Portland fish store
- Aqua Huna Freshwater fish, shrimp and plants with a three day live arrival guarantee
- The Shrimp Farm Freshwater shrimp, snails and crayfish with a live arrival guarantee
…or ask your local fish store.
Appears in
Keeping Assassin Snail?
Track water tests, reminders and stocking fit.
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