Assassin Snail: Care, Diet, Breeding, Calcium & More

The Assassin Snail (Anentome helena) is a popular freshwater snail that is also known as the bumblebee snail. They are called bumblebee snails because of the vibrant yellow and black stripes on their shells. They are famous for their beauty as well as for hunting other snails. This snail will continually move around in the tank and hunt when hungry. Most aquarists keep assassin snails to eradicate other pest snails or balance out their reproduction. 

The Assassin Snails are highly specialized hunters that can help you remove pest snails from your community aquarium. That said, they will only hunt when they are hungry so don’t expect them to hunt all the pest snails in your tank in a week or two. 

Here in this article, you’ll learn the correct Assassin Snail care guidelines and all the other information you need to keep them happy. 

Species Profile & Overview

The Assassin Snail is without a doubt one of the most gorgeous freshwater snails in the aquarium hobby. They belong to the Nassariidae family of snails and are endemic to Southeast Asia. They are found in large numbers in Thailand, Malaysia, and Lake Toba in Indonesia. Their distinct look and their hunting abilities make them an excellent choice for aquariums that have snail overpopulation problems.

These snails have a beautiful cone-shaped shell that is painted beautifully. This makes them a desired snail even for those who don’t have snail problems in their tank. Unlike most snails, they do not eat algae or plant-based foods so you will need to make sure they receive food in your tank. 

Assassin Snails are almost always available in pet stores as they are in high demand in the aquarium hobby. This makes the Assassin Snail somewhat pricey in comparison to more regular types of freshwater snails. 

Assassin Snail is often collected in the wild and sold in pet shops. This is due to the fact that they are readily available in the wild and it is financially viable to collect them in the wild than breed them in fisheries. That said, there are also breeding facilities and local breeders who breed these snails for the pet trade. 

Assassin Snails are mostly active during the daytime but will also actively hunt at night. Since they are carnivorous snails, they will only reproduce to the amount of food(other snails) available in your aquarium. This makes them easy snail to manage. 


Assassin Snail (Anentome helena)

Assassin Snail is beautifully painted in black and yellow stripes that make them seen in your tank. This coloration and pattern is the reason they are called “Bumblebee Snails” sometimes. They have a cone-shaped shell that has a small opening that lets them come out. The shell is very hard and can withstand a lot of pressure. 

Their body is generally creamy white, yellow, or gray in color. Some might have small patches on their body but most are creamy white. They also have a trap door (operculum) attached to their body that helps them block the shell’s entrance. 

They have 2 tentacles on their head near the eyes that help them feel the hormones in the water. This is how they “Smell” in the water. They also have a third tentacle-like tube (Siphon) that acts as their breathing organ. They also have another tentacle-like organ known as “Proboscis” that comes out of their mouth when they hunt. The Assassin Snail will shoot its Proboscis into the shell of its prey and kill it. 

The Proboscis has no venom or enzymes to help with killing the prey, instead, it has sharp teeth that will cut through the flesh of the other snail. 

Assassin Snail Size

The average Assassin Snail size is 0.8 – 1.25 inches. There are no visible differences between male and female individuals and their size fully depends on genetics and food availability. In rare cases, some Assassin Snails might grow a little bit larger but it only happens in rare cases and with proper care and diet. 


In a well-maintained tank, the Assassin Snail’s lifespan is around 2 years. They may even live longer if they receive good care throughout their lifespan. Water quality has a direct impact on the lifespan of your assassin snail so make sure to keep your aquarium in pristine condition.

Behavior & Temperament

Assassin Snails are very aggressive hunters and will kill and eat any snail, fish fry, and fish eggs that come on their way. They will also go after larger species like shrimps and fish if they are sick and slow. But they will not hunt or hurt healthy fish or shrimp. 

They usually keep their body buried in the sand and substrate while keeping their siphon out for breathing. When They feel hungry they will come out and keep looking for any slow-moving living organism that they can hunt and eat. 

They mostly stay at the bottom of the tank where they hunt and bury themselves in the substrate. Although they are most active during the day, they will also scavenge at night. Assassin Snails are very slow-moving snails so they tend to stay where they feel safe and where food is mostly available. 

Despite being carnivore predatory snails, the Assassin snails will not hunt their own kind so you will need to feed your Assassins if your tank runs out of pest snails.

Assassin Snail (Anentome helena)

Assassin Snail Care

Assassin Snail care isn’t a challenging task and anyone can keep them in their aquariums. These snails are one of the easier aquarium species to care for. They can be in a species-only aquarium or a community tank with other aquarium fish. They will easily adapt to most water conditions in most tanks. This makes them very easy snails to keep.

Having said that, these snails need specific water parameters to be able to thrive. They will also need a sustainable source of live food so they can exercise their hunting skills. They also appreciate stable water parameters, fluctuating water parameters are a big risk to their overall health. Below are the minimum requirements for your assassin snail to thrive. 

Tank Size

The minimum tank size for a single Assassin Snail is 10 gallons. Since these species are one of the smaller types of aquarium snails, it is possible to keep them in smaller aquariums with other fish. Having said that, it is best to have them in a larger tank that is fully cycled and aged.

Tank setup is super important when it comes to snails. Assassin snails, unlike fish, can not swim in the water column. They need more surface area in the form of decorations and plants. This is especially true if you want to have multiple assassin snails. The more surface area you can create in your tank the more snails you can keep. More on this is below in the “Tank Setup” section.

Tank Setup

The tank setup and the decorations you place in the tank can make or break your efforts of keeping Assassin Snails. These snails are sensitive to changes in water parameters and the Chemistry of the water. This means you have to have a balanced and well-cycled tank that has the right decorations. 

Each item you place in your aquarium has the potential to change the chemistry of the tank’s water. At the same time selecting the right decorations can give your snails and fish a stable space to thrive. When selecting decorations, always go for natural decorations if possible. Natural decorations will help you maintain balance in your snail tank. They are also an easy and appealing way to give your snails more surface. 

Live plants, natural rocks, and driftwoods are the ideal decorations to place in your tank. As mentioned, they will give your snails more surface area to explore while balancing your aquarium parameters. This can be a very rewarding and pleasant thing when done right. 

The substrate is another important topic to consider. Assassin snails bury themselves in the substrate, so they will need a soft substrate to crawl under, sand is the best substrate for Assassin snails as they can easily bury themselves and hunt. Some soft-planted substrates are also great choices for your snails and your plants. 

To create a stable ecosystem for your Assassin snail and your fish, we highly recommend planting aquarium plants. Plants will help your tank by removing waste and other toxins created by your snails and other inhabitants in the tank. At the same time, they make your tank more beautiful and will give your snails more surface area to explore. 

Calcium For Assassin Snail

The soft body of Assassin Snails are protected but their hard shell. Their shell is mainly made of calcium and it’s the only defense mechanism they have against predators. This means they need to have calcium in their diet to grow and maintain their shell. 

Calcium makes up 98% of their shell and the remaining 2% is other elements that cause the different colorations on the shell. 

Fortunately providing calcium for your Assassin snail is easy and cheap. The most simple and easy method to add calcium to your tank is by placing a few empty egg shells in your tank. The eggshell method is what we mostly use in our own snail tanks, it’s easy, simple, and budget-friendly. That said there are also commercially made calcium supplements for aquariums that are designed to provide the best results. Cuttlebone is also another famous way to add calcium to your water. Cuttlebone is a sustainable source of calcium that you can easily buy from the birds’ section of most pet stores. 

Water Parameters

Assassin snails are endemic to tropical regions of Southeast Asia so they will need a similar water temperature. In the wild, they live in warm shallow parts of the lakes and rivers. These areas are usually clear so that light can reach in and plants can grow. Plants and algae will keep the water clear and clean and create a lot of hiding spots for small creatures. In an aquarium environment, your Assassin Snail needs the same balanced and steady water parameters. Below are the ideal tank parameters you can keep your Assassin Snail in: 

  • Temperature: 72 – 80 Degrees Fahrenheit 
  • PH: 6.5 – 8
  • TDS: 100 – 200 PPM

The above-mentioned parameters are the “ideal” parameters you can keep your assassin snails in. However, they can tolerate slightly lower or upper parameters but will not thrive. Regular water changes are very important to the health of this snail. This is because water changes will keep your water parameters stable. Stable water parameters are more important than chasing a perfect number on a pH meter or TDS meter. 

Filtration System

Assassin Snails are a predatory type of snails and will constantly hunt in your tank. This means they will produce a lot of waste in your tank. Each time they hunt, they will eat as much as they can eat in a single meal and leave the rest to rot in the tank. This means you will need a powerful filter to maintain clean water in your aquarium at all times. 

Assassin snails are extremely vulnerable to ammonia spikes and low water quality. They can develop different types of diseases when water parameters are not in mint conditions. A good filter plus regular water changes will keep your aquarium in pristine condition. 

Common Diseases & Prevention

While some snails can have species-specific diseases, the Assassin snails seem to have no particular disease. However, this doesn’t mean that they will not get sick in a tank environment. These snails are vulnerable to most known aquarium diseases caused by poor water quality. An aquarium is a tiny ecosystem that an epidemic can easily take over if a fish or snail gets sick.

Copper is the most deadly poison for Assassin snails. Lower doses of copper can eradicate an entire tank of snails. You have to check every time you’re adding to your tank for copper, this includes decorations, food, and medicines. 

They are also at risk of getting the soft-shell disease. When Assassin snails do not receive enough calcium in their diet they will slowly lose the firmness of their shell. To prevent this, you should add calcium manually into your tank. We recommended a few ways of supplementing calcium above in the “Calcium For Assassin Snail” section of this article.

As always, prevention is easier than cure. Having a well-maintained tank with all the elements your fish and snails need will prevent most diseases. This will also save you a lot of money by not having to buy medications to treat your tank. 

Diet & Feeding Requirements

Feeding your Assassin Snails is one of the most important care principles of this species. These snails are carnivores (meat-eaters) and predators that hunt any slow-moving small creature that they can catch. However, your tank might not have enough pest snails or after some time your tank might run out of snails so it is important to have some carnivore sinking pellets around. 

Assassins are famous for hunting slow-moving snails like Ramshorn Snails, Malaysian Trumpet Snails, and Bladder Snails. They are easy targets for Assassin Snail that it can easily hunt. Assassin snails are also seen to go after larger snails like Apple Snail, Nerite Snail, And Mystery Snail. They will also hunt any small creatures that move slowly like shrimplets and fish fry or even their eggs.

However, Assassin Snails will not hunt other assassin snails and will not eat their own eggs. This makes it easy to keep and breed them. More below in the breeding section.

If you run out of pest snails in your tank you can feed your Assassin Snails with different types of commercially produced dry foods. Any carnivore sinking planet or flakes seem to do the work so pick what you have available in your local pet store. 

You can also feed them frozen bloodworm or brine shrimps but make sure these foods actually reach your snails if you have other species in the tank. 

Breeding Assassin Snail

Breeding Assassin Snail in captivity is super easy and effortless. In order to breed this species of snails, you will need to keep your water parameters stable and have plenty of food available for them at all times. You will also have to have a group of 5 – 10 of them in your tank. 

Unlike Mystery Snails, Assassin snails can not change gender, so you will have to have males and females in your tank so they can breed. Since there are no visible differences between males and females it is best to buy a large group of them to get at least one male and female. 

Unlike other snails that lay a cluster of eggs, Assassin Snail’s eggs are laid one at a time in close proximity. They lay their eggs on any available surface like aquarium glass, decorations, and plants. The eggs are light yellow right after they are laid but will slowly turn into a brownish color

The females lay a few eggs at a time and It will take up to 2 months for the eggs to hatch. This makes assassin snails one of the slowest snails to breed. So they will not take over your tank like other pest snails. 

Tank Mates

Assassin Snails are predatory snails that will hunt any slow-moving small creatures so they are not ideal snails if you have a breeding tank or a tank that has your favorite snails. However, they can not cause any damage to larger or fast-moving species. This makes it easy for you to pick tank mates for this snail. 

While assassin snails can kill smaller species, they themselves can become a good meal for aggressive and carnivore fish. So it is important to have them in a peaceful tank with other species. Here are some of our recommendations for Assassin Snails Tank mates:

Assassin Snail (Anentome helena)


Assassin Snail is a beautiful predatory snail that can help you get rid of pest snails in your tank. Since they breed slowly and in low quantities, they will not take over your tank. Always make sure your water parameters are stable and never overfeed. Only keep your Assassin snail with species that need the same care requirements. Doing this will create a healthy habitat for your Assassins and their tank mates. 

Congratulations! Now you know everything about Assassin Snail care and you can confidently own a few of them.