Assassin Snail Care: Diet, Tank Mates, Lifespan

The assassin snail is a popular freshwater snail often kept as a pet in aquariums. Their main purpose is to keep other freshwater snail populations under control. For example, assassin snails can help reduce ramshorn snails and trumpet snails population if they get out of hand. 2 to 3 assassin snails per 10 gallons is a good start for a tank overrun with ramshorn or trumpet snails.

Care Level:Easy
Color Form:Brown and Yellow Stripes
Lifespan:1-2 Years
Size:1-3 inches
Minimum Tank Size:10 Gallons
Tank Set-Up:Sandy Substrates, Adaptable
Compatibility:Community Aquarium
Species Overview

Assassin Snail Pictures


An Assassin Snail has a cone-shaped shell, like the shells of Malaysian Trumpet Snails and Rabbit Snails. Assassin Snail shells are gold in color with a warped dark brown stripe from aperture to apex. An Assassin Snail’s body and foot are a light cream color, with darker specks throughout.


Assassin snails are slow, so you won’t see much activity from them in your tank. They prefer to feed during the night so you may not see them during the day. However, if you feed them during the daytime, they will emerge to eat.

These snails spend most of their time buried in the substrate. Usually, they stay buried and wait for smaller snails to move above them before attacking.

Nonetheless, they are not aggressive toward fish. But, any slow-moving aquarium pet that is small enough may fall prey to the assassin snail.

Assassin Snail Lifespan

The average lifespan of a well-fed and healthy assassin snail is about two years. With the right water parameters and plenty of food, assassin snails can live for up to five years.

Assassin Snail Diet

Assassin snails are carnivores. They feed on other snails. Malaysian trumpet snails and ramshorn snails are particular favorites. They do not eat other assassin snails. They will often eat small snails as they move above them and can sometimes attack larger snails.

Assassin Snail Size

The average size of an Assassin Snail (in a store) is generally about 3/4 of an inch long. A fully mature, healthy, and well-fed Assassin Snail can grow to be up to 3 inches.

Assassin Snail Reproduction

Assassin snails lay yellow eggs that they deposit on a hard surface like the aquarium glass and aquarium decorations. They tend to lay one egg at a time and the eggs are usually near each other. It takes about two months for the eggs to hatch.

Assassin Snail Eggs.
Assassin Snail Eggs.

Assassin Snail Tank Mates

Freshwater aquarium fish like:

Some species of aquarium shrimp:

Be sure that the freshwater shrimp are larger than the assassin snail and that the snail is otherwise well-fed. You can also keep freshwater clams like the Asian Gold clam in the same tank as assassin snails.

Assassin Snail Tank Size

Assassin snails do best in tanks of at least 30-gallons in size. A larger tank works best because these snails grow to rather large sizes. Not only that, but they also feed on other snails. So, the tank needs to be big enough to keep other snails as well as the assassin snail population.

Assassin Snail Water Parameters

Assassin snails prefer stable water parameters. The tank should be filtered and heated. You should keep ammonia and nitrite levels at 0 ppm. Nitrate levels should also be kept low. If you add fertilizer or medication to your aquarium, make sure that they do not contain copper or other irritants that can kill snails. Aim to keep the water conditions at:

  • Aquarium pH: 7.0 – 8.0.
  • Temperature: 75 – 80 Degrees Fahrenheit.
  • Hardness: Hard.
  • Lighting: Adjustable.

Things To Consider

How To Buy Healthy Assassin Snails

As with other species of freshwater snails, you should look for active assassin snails that cling to hard surfaces. The color of the assassin snails’ body should be a creamy color. They often have darker specks about their body. They should have two tentacles with an eye at the base of each tentacle.

A healthy assassin snail’s shell is gold with brown stripes. There should be no cracks or signs of damage to the shells.

Do not buy snails that are kept in tanks with other dead snails or dead aquatic animals. Do not buy snails that are floating or not stuck to a hard surface. Snails that are motionless on the tank bottom are more than likely dead.

Live Plants

Assassin snails do well in planted tanks. They do not eat plants, and thus, live plants can thrive in the same aquarium. Sometimes, other species of snails may enter your fish tank attached to plants without your knowledge. Assassin snails can help get rid of/or keep these snails in check.


Dead assassin snails sink to the tank bottom. If your assassin snail is at the bottom of the aquarium and has not moved in quite some time, it is more than likely dead. The shell of the assassin snail may start to thin, and holes can form. It’s best to remove the dead snail from the tank.

Frequently Asked Questions

Do Assassin snails kill other snails?

Assassins snails eat other snails, but these are usually only smaller species. If you add different snails to your aquarium, they need to be the same size or bigger.

How Do Assassin Snails Kill?

Assassin Snails have a mouth and rasping radula that extends into the shells of other snails. The radula is like a scouring pad, slowly grinding flesh and blood and weakening their prey. Other Assassin Snails can pick up on the scent of an attack and work together to bring down even larger snails.

Do Assassin snails eat snails?

Assassin snails prefer to eat Malaysian Trumpet Snails, Ramshorn Snails and small pond snails. However, snails bigger than assassins are generally safe. They will often eat small snails as they move above them.

Do Assassin snails reproduce asexually?

Assassin snails do not reproduce asexually. In order to mate, there must be a female and male assassin snail. The female only lays a single egg at a time.

Do Assassin snails kill fish?

Assassin snails are not snail-eating fish, so they are harmless to fish, but they may eat their eggs.