Assassin Snail: Friendly Guide to the Little Predator

Are you a fan of intriguing freshwater critters that can add a touch of uniqueness to your aquarium? Look no further than the assassin snail, a fascinating creature that brings beauty, hardiness, and a practical function to any aquarium.

Assassin snails (Anentome helena) are easily recognized by their yellow and dark brown banded trumpet shells. With their ease of care and natural ability to feast on other unwanted pest snails, they make for an excellent addition to tanks of all sizes.

In this article, we’ll take you through everything you need to know about providing a suitable environment, fulfilling their dietary needs, and ensuring the wellbeing of your assassin snails. Get ready to enjoy the company of these amazing invertebrates as you level up your aquarium expertise.

Species Overview

Assassin Snail

Property Value
Scientific name Clea helena, Anentome helena
Common names Assassin Snail, Bumblebee Snail
Distribution Southeast Asia
Size 0.8-1.25 inches (2-3 cm)
Lifespan Up to 3 years
Diet Carnivore (predominantly other snails)
Temperament Peaceful, opportunistic predator
Minimum tank size 10-15 gallons (37-57 liters)
Temperature 70-80°F (21-27°C)
pH 7.0-8.0
Water hardness 2-12 dKH
Care level Easy to moderate
Filtration/Water Flow Moderate
Water type Freshwater
Breeding Egg-laying
Breeding difficulty Moderate
Compatibility Compatible with non-aggressive fish

Assassin snails are small invertebrates native to Southeast Asia. They primarily consume other snails, which makes them a unique addition to your aquarium. Given the right conditions and care, they can live for up to three years.

Despite their predatory nature, assassin snails do not harm aquatic plants, making them a desirable addition to planted tanks. They are typically less active during midday and become opportunistic hunters in search of prey.

In your aquarium, maintain proper water parameters, provide ample hiding spots, and ensure moderate water flow. This will contribute to your snail’s well-being and promote a healthy environment.

Breeding assassin snails is moderately challenging. They’re egg-laying creatures, and by providing suitable conditions, you can potentially witness the breeding process in your tank.

Assassin snails are compatible with non-aggressive fish. Always take care when introducing them to an aquarium community to ensure a harmonious ecosystem.

Assassin Snail Basics

Origins and Natural Habitat

Assassin snails, or Clea Helena, are native to Southeast Asia. They originally dwelled in the tropical freshwater environments of Thailand, Malaysia, and Indonesia. In these habitats, you would typically find assassin snails in rivers and ponds. They later became popular in the aquarium trade and were introduced to similar environments worldwide.

Size and Shape

Your assassin snail is a small and fascinating creature. Adults usually grow to a size of 1 to 1.25 inches (2.5 to 3 cm) in length. They have a unique cone-shaped shell, resembling the shells of Malaysian Trumpet Snails and Rabbit Snails.

Color and Markings

The assassin snail is quite attractive with its gold-colored shell, adorned by a dark brown stripe that spirals from the aperture to the apex. This distinctive pattern sets them apart from other snails in your aquarium.


In a well-maintained aquarium, assassin snails can live up to 2-3 years. To keep your snail content and healthy, make sure to monitor water parameters, maintain cleanliness of the tank, and provide a diverse diet of different types of snails and invertebrates.

Diet and Feeding

As an Assassin Snail owner, it’s essential to understand their diet and feeding habits to maintain a healthy environment for them. Assassin Snails primarily feed on other snails, particularly focusing on Malaysian Trumpet Snails, Ramshorn Snails, and pond snails. Snails without an operculum, like Ramshorn Snails, are especially vulnerable to their attack.

While their main focus is on snails, they may also consume soft snail eggs, shrimp fry, and surprisingly not their own eggs. However, larger snails like Mystery Snails and Nerite Snails are generally safe, but their young ones might be at risk.

Assassin Snails can also eat fish flakes, blood worms, and other protein-rich supplements. They can scavenge for meaty debris and dead fish in your tank. Besides, they do not eat live plants, making them a perfect addition to a planted tank. Since they control pest snail populations, they can be beneficial for your aquarium’s overall well-being.

In order to keep your Assassin Snails thriving, provide them with a balanced high-protein diet. They won’t clean the glass or eat algae like some other snail species, so you should not rely on them for that purpose. Interestingly, overfeeding is not a concern, as they have self-control and pace themselves accordingly.

To sustain your Assassin Snails, you can provide feeder snails. Be cautious when introducing ornamental shrimp to your tank, as hungry Assassin Snails may target them.

Behavior and Temperament

As a proud owner of Assassin Snails, it’s important to understand their behavior and temperament. These fascinating creatures are quite solitary, preferring to keep to themselves rather than interact with other tank inhabitants.

You’ll likely notice that your Assassin Snails are more active during nighttime hours. This nocturnal behavior reflects their natural habitat. During the day, they tend to hide in the sand, blending seamlessly with their surroundings and waiting for prey.

It’s completely normal for your Assassin Snails to conceal themselves in the sand, so don’t be alarmed if they’re not visible all the time. This is a typical behavior for many snail species, including these bumblebee-striped critters.

Despite their carnivorous appetite, Assassin Snails are quite peaceful and non-aggressive. They usually don’t interact with other creatures in your aquarium, such as fish or shrimp. So, you can rest assured that these snails will maintain harmony within your community tank.

Care and Tank Requirements

Tank Size

For Assassin Snails, it’s recommended that you start with a 10-gallon tank as the minimum size. If you plan to have more snails, adding an extra 5 gallons for every two snails will ensure they have enough space.

Water Parameters

To create an environment similar to their natural habitat, maintain tropical water conditions with a temperature between 70-80°F. The pH levels should range from 7.0-8.0, and water hardness should be between 2-15 dKH. Remember, stable water parameters are crucial for the well-being of your snails.

Tank Setup and Decorations

Make sure to use a soft sand substrate in the tank, as Assassin Snails enjoy burrowing and hiding within it. Decorate your aquarium with rocks, driftwood, and live plants that are safe for them to explore and climb on. Sturdy plants like Amazon swords and anubias are ideal options.

It’s important to note that Assassin Snails are carnivorous and won’t harm your plants, so feel free to add live plants to enhance the tank’s aesthetics and keep your snails entertained.

Filtration and Aeration

In order to maintain water quality and remove any harmful substances (like copper), a filtration system is crucial. Simple sponge filters are effective, affordable, and a great choice for supporting the well-being of your Assassin Snails.

Don’t forget to use a heater for consistent water temperature, maintaining it in the mid to high 70s. Additionally, regular water changes and low nitrate levels are essential for the health of your Assassin Snails.

Keep these care tips in mind, and your Assassin Snails will thrive in a well-maintained tank with a lifespan of up to five years.

Suitable Tank Mates

Assassin Snails thrive in a peaceful community aquarium setup. To ensure a harmonious environment, it’s essential to choose the right tank mates for these unique critters.

You can comfortably house Assassin Snails with others of their kind and most community tank fish. Ideal tank mates include gentle community fish that occupy the upper parts of the tank, such as Neon Tetras, Corydoras Catfish, Guppies, Cherry Barbs, Angelfish, Pearl Gourami, and Celestial Danios.

They also coexist well with peaceful scavengers like Cory Catfish and delicate algae eaters like Otocinclus Catfish. You may even consider adding small freshwater clams, larger Asian Gold Clams, Viper Shrimp, Bamboo Shrimp, Amano Shrimp, and Ghost Shrimp. However, when keeping them with freshwater shrimp, ensure the shrimp are larger and your snails are well-fed to prevent predation.

We’ll suggest you avoid housing Assassin Snails with rough types such as Cichlids, aquarium crayfish, Goldfish, or any tank mates that may injure or eat them. Additionally, you should not mix them with ornamental snails (like mystery snails and nerites), large aggressive fish, loaches, and pufferfish.


Breeding Assassin Snails is an interesting and rewarding experience. To start, make sure you have at least six snails in your tank to increase the likelihood of having both male and female snails, as they have defined sexes and are not hermaphroditic. You may notice their mating ritual, during which they pair up and follow each other for hours.

Assassin Snails lay one yellowish egg at a time, often close to each other. These eggs are contained in a translucent, rectangular-like enclosure and turn light brown after a few days. It takes about a month for the eggs to hatch, and during this time, you’ll likely see the baby snails inside the eggs before they’re ready to emerge.

Once hatched, baby Assassin Snails tend to burrow in the substrate as they mature. It will take about 2-3 months for them to grow larger, but don’t worry about them overrunning your tank, as they reproduce more slowly than pest snails.

Keep in mind that Assassin snail eggs can easily be transported to other tanks, so exercise caution to prevent accidental introduction to local waterways. Maintain a friendly environment in your aquarium and enjoy observing the fascinating process of Assassin Snail breeding.

Common Diseases and Treatments

Assassin Snails, like fish, can get sick and are susceptible to diseases. One common issue in Assassin Snails is parasitic infections, which often appear as white spots on the shell. Treating these infections is challenging as many treatments used for fish can be lethal to snails.

Various parasites can infect Assassin Snails, limiting your treatment options. If you notice any signs of infection, it’s best to separate the sick snails from other fish in the tank to prevent spreading the infection. Prevention through excellent care and maintaining high water quality is crucial in minimizing the risk of diseases.

Providing a healthy environment reduces the chances of Assassin Snails getting sick significantly. Taking steps to prevent diseases, such as regular water changes and monitoring water parameters, is the most effective approach. Regular observation and prompt action can help you catch and treat any potential illnesses in your Assassin Snails, ensuring their continued health and happiness.

Frequently Asked Questions

Will assassin snails eat my fish?

Assassin snails are primarily known for consuming other snails. They are not generally known to eat fish. However, it’s important to keep an eye on your tank, as these snails may target very small, slow-moving fish or weak fish.

Can a single assassin snail reproduce?

No, your assassin snail cannot reproduce on its own. They require a male and female snail for breeding. If you have a pair, they can lay eggs and produce baby snails over time.

Do these snails consume all types of snails?

Assassin snails are pretty effective at consuming various kinds of smaller snails, which makes them great for controlling pest snail populations in your tank. They especially target snails like bladder snails, Malaysian trumpet snails, and pond snails. However, larger snails, such as mystery snails and nerite snails, are usually safe from assassin snails due to their size and shell thickness.

Can they overpopulate a tank?

Unlike some other snail species, assassin snails typically do not overpopulate a tank. Their reproduction rate is relatively slower, and since they require a male and female for breeding, their numbers tend to be more controlled. Keep in mind that the number of baby snails produced will depend on the number of adult snails in your tank and the availability of food.

Do they help in cleaning the tank?

While assassin snails do help in controlling pest snail populations, they do not contribute significantly to cleaning the tank. They do not consume algae like some other snail species. For better tank cleaning results, consider adding some algae-eating species, such as nerite snails or shrimp, to your aquarium.