The unique Assassin Snail is a fun, interesting critter to watch and add some color to your aquarium or paludarium – so it’s really no wonder that these little guys have become a popular freshwater snail for aquarists. They also help to keep other freshwater snail populations under control, preventing overcrowding of the tank.

These little guys are the go-to for many hobbyists (and should be considered for your own go-to method!) for getting rid of hitchhikers snails (especially Malaysian trumpet snails and ramshorn snails, and pond snails) and other pest snails, overpopulated invertebrates, et cetera. Your initial thoughts might be, “why am I adding more snails?!” But they live up to their name – and that makes them valuable for many situations. They also make excellent pond snails for those unseen depths.

Plus, they’re attractive and have spunky personalities (for snails), won’t eat your plants, and overall are a nice addition to your fish tank.

Quick Intro to Assassin Snails

Family: Buccinidae
Scientific Name: Clea helena
Other Names:Anentome helena, Bumblebee snail
Care Level: Easy

Natural Habitat, Identification, and Where to Buy

Assassin snails are a type of freshwater snail with an operculum that is a part of the Buccinidae family. While there are several snails called “whelk”, the Buccinidae family is the only snail family which has the true whelks, which is the proper name for carnivorous snails.

The snail has earned its name due to its eating habits. They are known to target, kill, and eat other small snails. This species of snail is native to southeast Asia and can be found in the lakes and rivers of Indonesia, Malaysia, and Thailand.

This snail is extremely popular among home aquariums, so much so that it has resulted in them becoming an invasive species. There is great concern that they will continue to spread and wipe out native life due to how aggressive this snail can be.

A great thing about this snail species is that it is quite easy to care for. They are so easy to take care of that a beginner fish keeper should have no problem caring for them. The biggest thing this species need is a clean tank, with that requirement met they can mostly take care of themselves. Another great selling point of this snail is that on average they run for $2 a piece but if you buy in a large quantity their price tends to be lower.

Tips for Buying Assassin Snails

When looking for the right Assassin Snails to purchase, it is important to pick active snails. This type of snail-like to affix to surfaces like decorations or the aquarium glass.

It’s normal for this snail to have a gold color with a brown stripe wrapping around it. The shells should be free from obvious damages or cracks.

A healthy Assassin Snail will have a foot that is a light cream color and covered in dark specks. It will have two tentacles with an eye on each.

When looking to buy, pay attention to the tank. If there seems to be a large number of sick or dead snails, it would be a bad idea to purchase from that tank. Also, it is important to make sure the snail you purchasing isn’t just an empty shell.

You’ll find them online at:

Optimal Water Conditions for Assassin Snails

Water Temperature: 70-80°F
Water Flow Rate:Slow
Water Hardness:8-15 dGH

Tank Setup

Minimum Tank Size10-gallon tank
Optimal Tank SizeTwo snails per five gallons of water
Optimal Tank Shape:Normal
Recommended Filter Type:Normal tank filters are fine

Assassin Snails dwell in southeast Asia. The water that these snails live in is both slow moving and tropical. The waters tend to slightly alkaline and well lit. The rivers that this snail lives in has a substrate that is a soft sand. This substrate allows the snail to bury themselves as needed.

The rivers that these snails are native to also have mini cave systems formed for them by various debris and rock in the water. While there are a variety of plants located in and around the water, this species of snail has no interest due to being a carnivore.

To make sure your snail is healthy and happy; it is important to create a tank that closely replicates their home waters.

When choosing the substrate for your tank, sandy is important. Most of the snail’s time is spent in the substrate so it is important to get this right. If the substrate is too hard it can damage this snail’s extremely sensitive tentacles.

If you wish to place pants in the tank there are no specific ones that the snails like or dislike. The snails do not use plants for shelter or food and ignore the plants. This apathy towards plants makes them perfect for being placed inside tanks dedicated to plants.

Additional decorations in a tank is always a personal choice but you can place them in the tank. The right decorations can give the snails a place to climb, explore and attach eggs while breeding.

The temperature should be kept between 70-80°F and a pH in the range of 7-8 with water that is kept slightly hard for encouraging the shell growth.

The minimum size tank should be ten gallons, but more room is always better. Two assassin snails should be kept per five gallons of water.

Creating the Landscape

As mentioned above, a tank with assassin snails needs to have a soft substrate that has plants. Unlike most snails, assassin snails will not attack the plants.

It is important to check to make sure before you plant any plants in your tank, it is important to make sure they are clean and are not carrying any other possible occupants. The plus side is if another snail sneaks into the tank, the assassin snails will handle them.

As far as decorations go, using rocks and driftwood is great. These allow you to build a small cave that your snails can explore. They will also enjoy climbing and seeing what all you have placed inside of your tank.

Regardless of what you decide to place in the tank, the sand needs to be soft enough for the snails. They like to dig into the substrate and cover themselves in the sand.

This type of snail does not require your aquarium to have a piece of specific or specialized equipment. There is no need for using air stones or a type of fast-moving pump. Normal filters can cause the water currents that this snail needs. 

One thing that you should pay attention to is how well your filter is acting. This type of snail needs to have water that is high quality. It is important to have sponges on your filter to prevent any escapes or accidents with your snails.

Having a good filter helps to remove the waste matter so it will not cause the water to become dirty. Regardless of your filter, it is important to replace a portion of the water every week.

Best Plants: Any kinds that work in a tropical environment
Best Lighting: Bright light
Best Decorations:Any which you find pleasing
Decorations to Avoid:None

Physiological Considerations for Assassin Snails

Size: Upwards of 3 inches fully grown
Lifespan2-3 years (with perfect living conditions up to five years)
Temperament: Peaceful
Preferred Tank Region: Bottom

One of the best things about keeping Assassin Snails is that they are easy to take care of and do not offer a lot of difficulties. The two things to watch for are to make sure your snails have easy access to food and ensure that their water quality is kept high.

Most stores that sell Assassin Snails will offer snails that are around 3/4ths of an inch long. If you keep your tank conditions correctly and keep the snails well fed, they can grow upwards of three inches long. It is important to take into count the possible size your snails could grow into before you purchase a large number of them.

Healthy Assassin Snails live around two years. The snails can live longer if their water conditions are kept perfect and they have access to the food they need. The longest reported lifespan of this snail species is around five years.

If you are interested in having a large collection of snails in one tank, you must have a big enough tank and keep a ratio of two snails per five gallons of water.

When first adding snails to the tank, make sure the water parameters and set and ready to go, otherwise it may cause your snail to be ill or possibly die. While adding snails to the tank, it is important to make this a slow process without rushing.


When you’re ready to get some assassin snails, beware that there are some compatibility concerns, the snails won’t attack the fish. However, a large number of fish will try to eat the snails.

The best fish to pick are community fish, small species that will swim in the mid-levels of the tank. Great examples of this type of fish include guppies, neon tetras, cherry barbs, and celestial danios. Avoid small fish that tend to hang out toward the bottom of the tank, as they may become dinner. Also, avoid aggressive predatory fish like cichlids, crayfish, or goldfish.

For those who want to put big fish in, there are some choices. Some bigger fish such as angelfish, rainbow fish, or gourami can all peacefully coexist with the snails.

You mustn’t pick fish that are bottom feeders, they have a high chance of attacking your snails.

Your assassin snails can coexist together peacefully, the key is to make sure you do not overstock and provide adequately for each snail. If you want to add other types of snails the best choice would be species that are bigger than assassin snails.

Fish tank mates that do well with assassin snails include:

Non-fish Companions:

Gender, Breeding, and Reproductive Considerations

For those who are wanting a large population of Assassin Snails or simply want to breed them in captivity, there is good news. This breed of snail is extremely easy to breed in captivity. Unlike many gastropods, this species has defined genders, but it is practically impossible to tell the male and female snails apart, especially as there are hermaphrodites in the species (meaning the snails contain both male and female reproductive organs).

Since you can’t separate the snails by gender it is important to have a large enough group to guarantee that you have the two genders necessary. Typically, a group of six snails is enough to have the odds work out and have at least one pair of snails.

Once they have decided it’s time to mate, it takes about twelve hours or so to happen. When the pair of the two snails will be stuck together. After mating the female will lay tiny eggs by attaching them to a hard surface. It will take about 20-30 days for the eggs to hard. After hatching the juveniles will burrow into the substrate until they are grown. It is normal to not see these again until after they have matured in six months or so.

While there aren’t any special conditions needed to help begin the mating process, it is important to make sure the temperature doesn’t drop. A low temp might cause the snails to be put off and prevent the laying of eggs.

Nutritional Needs

Assassin snails are a species that is a pure carnivore, so they do not need any vegetation to survive. For the most part, they simply ignore plants and algae. So this means that unlike most snails they won’t help reduce the algae in their tank.

Possible foods include other snails, shrimp fry, soft snail eggs, or even algae wafers.

It can be difficult to know the exact amount of food to feed the snails because they will eat at their own pace. Typically, 1-2 other snails a day would be enough food for them.

If you are wanting to keep other snails with your assassin snails they must be larger. However, if there is a lack of food and if the assassins become aggressive, they will start to target larger snails to eat. And if they run out of other smaller smails, they may go after nerite snails.

Foods they eat when they’re all out of snails to assassinate include bloodworms, brine shrimp, and protein-heavy sinking pellets.

Best Sustenance Food Type: Other snails and algae wafers
Additional Food For Optimal Health:N/A
Special Foods and Considerations for Best Color and Growth: N/A
When and How Often to Feed Fish Based on Life Cycle: Once a day

Common Diseases and How to Avoid and Treat Them

Snails, just like fish, are susceptible to a variety of illnesses.

The shells of a snail are capable of being affected by a few things. If you see white spots appearing on the shells, there is a likely chance the snail is dealing with a parasite.

Shell health is especially important, if it cracks, the snail will most likely die. While most snails get their calcium from their diet, you can give them calcium supplements in their water.

It is important to keep copper away from your tank. Most invertebrates, including snails, have a severe allergy to copper. There are a number of aquarium medications that contain copper, always double-check the ingredients before using them.

The best way to ensure the health of your snails is to keep the water quality high, the temperature consists and to examine everything before adding it to the tank to make sure there are no obvious pollutants that will be added to the water.

Best Antibiotics: Consult a vet.
Treatments to Avoid:Avoid any treatments with copper.
Food Recommendations When Sick:N/A
Hospital Tank or Isolation Withing the Community Tank:If you notice parasites it is important to isolate those affected and clean the tank.

4 Facts About Assassin Snails

  1. Assassin snails aren’t like other snails. They’re primarily meat-eaters. Carnivores instead of omnivores or herbivores like other snails!
  2. Because of their carnivorous ways, they lean towards eating other mollusks.
  3. These little snails are one of the most active aquarium snail species, which is part of why they’re popular and fun to keep.
  4. Yep – they’re named for their ability to and habit of hunting down and “assassinating” other mollusks for their dinner.

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