Assassin Snail Care: Diet, Tank, Breeding & Lifespan

Assassin Snails are a popular freshwater critter that many people want to own. Their neat patterns and low-maintenance nature makes them the perfect addition to many tanks!

They’re also great at getting rid of any pest snails that might be taking over your tank. Simply drop a few Assassin Snails in your aquarium and your problem is solved.

Because we’re such fans of this species we wanted to put together a dedicated care guide. They deserve it!

In this guide you’ll learn everything there is to know about Assassin Snail care. Diet, tank conditions, breeding, and more. It’s all here.

Species Summary

The Assassin Snail (Clea helena or Anentome helena) is a unique addition to freshwater tanks. While most other snail species are used exclusively for keeping ecosystems clean, these critters have a different claim to fame. They’re carnivores that like to feed off of other snails!

As such, they’re often introduced to tanks that are overrun by pest snails. Even a small collection of Assassin Snails can take care of a large colony of smaller species in a few weeks.

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Originally found throughout Southeast Asia, Assassin Snails have become very popular among aquarists. Not only do they serve a practical purpose in fish tanks, but they’re very easy to care for.


The average Assassin Snail lifespan is somewhere between 2 and 3 years. While that is the norm, some enthusiasts have reported these gastropods living for upwards of 5 years!

Tank conditions and diet play a big role in their overall health and lifespan. These snails have a unique diet that needs to be fulfilled. Otherwise, they might not even make it to the 2-year mark.


Whether you plan on using an Assassin Snail to control the snail population or not, they sure are a joy to look at. Unlike other snails that have a bland shell, this species has some color to it. The shells feature brown and yellow stripes. This has lead to the nickname “Bumblebee Snail.”

The shell pattern of an Assassin Snail

Some snails do have a solid brown shell, but it’s quite rare compared to the stripe pattern.

The shell itself has some unique properties as well. It’s conical and features a blunt point on one end.

When the snail feels threatened, it will retreat back into its shell for protection. The interesting thing about this behavior is that the snail is fully capable of staying safe from most small predators. That’s because it has an operculum. Basically, it’s a trap door that allows the snail to seal itself off in its shell.

To get around the tank, the Assassin Snail has a very muscular foot. It contracts to help the critter navigate its surroundings. Of course, the snail’s movements are slow and steady. You can often find the snail clinging onto the glass or moving up rocks.

The snail’s body takes on a light beige hue. It’s covered in brown and black specks, which undoubtedly help the snail blend in with the substrate.

On its head, you’ll see two short tentacles. The eyes are located on the ends to help the snail detect light and motion.


In captivity, the average size of an Assassin Snail is about one inch in length. Some can get up to 2 inches long with the right diet, but that’s quite uncommon.

Author Note: Despite their small size, these critters tend to have quite the presence in your tank. Their neat appearance more than makes up for their diminutive nature!

Assassin Snail Care

For the most part, Assassin Snails are very easy to take care of. They’re very low-maintenance and can thrive without much fuss.

The priority requirements are good tank conditions and plenty of nutritious food. Failing to provide this significantly increases the chance of illness and a shortened lifespan. Here are some of the most crucial care tips you need to follow.

Tank Size

Realistically, you don’t need a huge tank to give Assassin Snails a fulfilling life. Because of their tiny size, they’ll do just fine in a moderately-sized tank with plenty of places to explore.

At the very least, they should be kept in a 10-gallon tank. It’s recommended that you add 5 gallons to that size requirement for every two snails you own.

In general of course, a bigger tank is always better. Many Assassin Snail owners prefer to stick these gastropods in tanks up to 30 gallons in size so they feel like they’re in an open space and have no need to try and escape.

Author Note: If you’re an owner who’s committed to maximizing the lifespan of your Assassin Snails, we highly encourage you to get a tank that exceeds the minimum recommended size. These creatures thrive when they have room.

Water Parameters

In the wild, Assassin Snails can be found in tropical climates. They live in slow-moving rivers filled with soft sand and plenty of rocks. Rivers in Southeast Asia tend to be a bit alkaline, so the snails fair best in water conditions that mimic this quality.

Temperatures should be on the warmer side. Any significant shift into a cooler temperature range can lead to shell problems and death.

  • Water Temperature: 70 to 80 degrees Fahrenheit (aim for the middle)
  • pH Levels: 6.5 to 7.5
  • Water Hardness: 2 – 15 dKH

What To Put In Their Tank

The good news is that you don’t have to do much to please Assassin Snails! The gastropods spend most of their time at the bottom of rivers when they’re in the wild. They’ll do the same in captivity.

It’s important to know that these snails like to dig and hide. Because of this, the substrate should be loose enough to let them slowly cover themselves.

This means you’ll want to have a fine sand substrate at the bottom of your tank. This is soft and easy for them to burrow in. Using a large or coarse substrate can cause damage to their tentacles and skin.

For the most part, a sandy substrate is the only high-priority requirement for Assassin Snails. You can feel free to decorate the rest of your tank how you like.

We like to go the extra mile when it comes to our critters, and we think you should too. Including some rocks and climbable driftwood is something we highly recommended since it gives these snail places to explore.

Plants are welcome, too. Usually, keeping plants with snails is a bit risky. They’re prone to eating and destroying them. However, that’s not the case with Assassin Snails.

This is because these snails are carnivorous. They really don’t care one way or another if you have plants!

When it comes to equipment, there are no strict requirements either. The movement caused by normal filters is more than enough current for these snails. You don’t need a fast-moving pump or air stones.

An assassin snail moving around substrate that isn't ideal

You should, however, pay close attention to how effective your filtration is. Assassin Snails need high-quality water to thrive. Invest in a good filter (like the FX4) to ensure that organic matter doesn’t muck up the water too much. Even still, you should be replacing a good portion of water every week.

Author Note: Since these little critters love to climb you should make sure that your tank is covered. Filters should also be equipped with sponges to prevent any accidents and escapes.

Common Possible Diseases

Don’t make the mistake of thinking that snails can’t get sick. They’re fully capable of suffering from diseases like fish.

One of the most common issues these snails have to deal with is parasitic infections. Usually, they appear as white spots on the shell. Unfortunately, treating these infections is easier said than done.

Many different kinds of parasites could infect Assassin Snails. Plus, most of the treatments used to heal fish are lethal to gastropods. For example, copper-based medications can kill these snails off quickly.

If you notice any signs of sickness your best bet is to separate the snails from any fish that could get infected. You don’t want your snail problem to affect the whole tank!

As always, prevention is the best way to handle diseases. If you provide great care and have impeccable water quality in their tank, the chance of your Assassin Snail getting sick goes down significantly.

Food & Diet

Assassin Snails are carnivorous and eat protein-based foods only. Their favorite type of food is actually other snails that are smaller than them.

They’re not picky either. These animals will attack any snail they can. Many owners feed them Trumpet Snails, Rabbit Snails, Ivory Snails, and Ramshorn Snails. Assassin Snails will also feed off of the eggs from other snail species.

If those aren’t available, shrimp fry and bloodworms do just fine. You may also find your snail snacking on brine shrimp or leftover flakes that fall to the bottom of the tank.

One nice thing about Assassin Snail care is that you don’t need to worry about overfeeding. Assassin Snails like to pace themselves and have a good amount of self-control (unlike a lot of fish).

This means you could realistically supply a good population of feeder snails and let the Assassin Snail eat slowly over time!

Behavior & Temperament

Assassin Snails are pretty solitary creatures. They’re more active at night and like to keep to themselves. If you don’t see the snail clinging onto the glass, they’re most likely hidden in the sand.

This is normal behavior that the snails practice in the wild. They hide in the sand and wait for an unsuspecting snail to walk on by.

Aside from their carnivorous nature, these snails aren’t aggressive at all and typically won’t even acknowledge other creatures. This is pretty par for the course when it comes to snails, and this species isn’t any different.

Tank Mates

Assassin Snails aren’t aggressive to fish (not surprising). The only thing you need to worry about is pairing them with tankmates that will see them as food!

The snails do best with gently community fish that occupy the upper parts of the tank. Bottom-dwellers can work too. However, they need to be gentle scavengers that won’t eat the snails.

Here are some of our favorite Assassin Snail tank mates for you o consider:

Assassin Snail Breeding

Assassin Snails have no problem breeding in captivity. In fact, they can multiply quickly if you have many kept in one tank!

Unlike other gastropods, these snails are not hermaphrodites. Defined sexes do exist, but it’s virtually impossible to distinguish the two by appearance alone.

You can keep a collection of 6 or more snails in one tank to increase the odds of successful breeding.

The snails have a bit of a mating ritual. The critters pair up and follow each other for several hours. This is a noticeable change in behavior as most snails don’t even acknowledge others in normal circumstances.

Once the Assassin Snails have mated, the female will lay eggs onto any firm surface she can find. It takes about a month for the tiny eggs to hatch. At that point, the babies will bury themselves in the sand until they get a bit bigger and are ready to emerge.

Adults usually don’t eat the young, so you don’t need to worry about separating them.            

Wrapping Up

Assassin Snails are a fantastic freshwater critter to include in your tank, plain and simple.

They’re easy to care for, look great, and will get rid of any pest snails that might show up in your aquarium. Basically, you get a bunch of benefits and zero drawbacks.

We highly recommend that you pick some up for yourself, but if you’re still on the fence feel free to let us know! We love talking about these animals and enjoy hearing from our readers.

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