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Will Assassin Snails Kill Mystery Snails?

With the number of people keeping aquatic snails in their aquariums being higher than ever, the number of questions that we have noticed people asking about the various types of snails you can keep in an aquarium has also started to increase.

After we published our article going over if assassin snails will eat nerite snails, we noticed more and more people reaching out to ask if assassin snails will eat mystery snails or not.

We have seen a number of people asking this on social media and getting totally wrong answers that put their mystery snails at risk so we have decided that we wanted to publish this article to try and help as many of our readers as possible.

Our hope is that we will be able to help you better understand the very real thread that even a single assassin snail can pose to your mystery snails in your pond or aquarium.

What Are Assassin Snails?

The assassin snail (Clea helena) is a species of freshwater snail that belongs to the family Buccinidae.

This snail is native to Southeast Asia and can be found in countries such as Thailand, Malaysia, Indonesia, and the Philippines.

The assassin snail gets its name from its diet which consists mostly of other snails.

In the wild, these snails help to control the populations of other snail species by preying on them.

The assassin snail is a very popular addition to many aquariums because it helps to keep the population of other snail species under control.

These snails are very easy to care for and they are not known to bother other fish or invertebrates in the aquarium.

What Are Mystery Snails?

The mystery snail (Pomacea bridgesii) is a species of freshwater snail that belongs to the family Ampullariidae.

This snail is native to South America and can be found in countries such as Brazil, Uruguay, and Argentina.

Mystery snails are very popular additions to aquariums and ponds because of their beautiful shells and their helpful nature, especially now that there are a number of rare color morphs available.

Mystery snails are known to help keep the aquarium clean by eating algae and other detritus.

Will Assassin Snails Kill Mystery Snails?

In almost all aquarium and pond setups that have both mystery snails and assassin snails in them, the assassin snails will end up eating the mystery snails.

We have seen a number of conditions on social media where people say that you can keep an assassin snail in the same aquarium as mystery snails without the assassin snail eating the mystery snail if certain conditions are met but this is not correct.

This is why we would always recommend that you avoid keeping an assassin snail in your tank with mystery snails unless you want to use the assassin snail to control the mystery snail population.

Baby Mystery Snails

Baby mystery sails are very easy prey for an adult assassin snail but even a juvenile assassin snail will usually be able to eat a baby mystery snail with minimal issues.

In many aquarium setups, assassin snails will go for the baby mystery snails rather than the adult mystery snails until there are no baby mystery snails left.

This is one of the ways that the assassin snails can help with mystery snail population control as they will eat a large number of baby mystery snails before moving on to the adults.

Even the mystery snail growth rate is usually not enough to help protect them as adult assassin snails will usually eat both baby and adult mystery snails with minimal issues.

Adult Mystery Snails

Although many people on social media commonly say that an assassin snail will not eat an adult mystery snail due to the size of the snail, this is not correct.

A mystery snail is defenseless against an assassin snail’s attack so the size of the mystery snail will not be able to help it.

Some people seem to think that the mystery snail will be able to retract into its shell for protection from an assassin snail but this is not correct as the assassin snail simply extends out of its shell to counter the mystery snail’s defense.

Although a single assassin snail will often eat adult mystery snails, there have been cases of multiple assassin snails ganging up on a single adult mystery snail to make it easier for them to take it down and eat it.

Why Do People Keep Assassin Snails With Mystery Snails?

There are two main reasons that people will keep assassin snails with mystery snails.

Population Control

The first reason is for population control as mystery snails really can breed at a rapid pace resulting in a rapid increase in the number of mystery snails that you have in your aquarium.

Even a single assassin snail is able to help control the population of the mystery snails in a small aquarium with ease.

If you have a large tank or pond then you will probably need at least three assassin snails to control the population of your mystery snails though.

As we mentioned earlier in the article, most assassin snails will eat large numbers of baby mystery snails but if they have no baby mystery snails left to eat, they will move on to the adults.

Just remember that once your mystery snail population is down to a more manageable number, you should look to remove your assassin snail if possible as they will just keep eating the mystery snails in your tank.

If you have rare mystery snail morph colors in your tank then we would highly recommend that you remove them prior to adding your assassin snail too as they will not care about how much you paid for your mystery snails and will still eat the expensive, rare color morphs without issue.

Accidental Addition To Your Tank

The popularity of keeping snails in aquariums has really seen a surge in its popularity recently and we have lost count of the number of people new to the aquarium keeping hobby or keeping snails in their tank who have purchased assassin snails for their look.

This is more common than you think and people have then added the assassin snail to their main community tank without realizing that they eat other snails.

This is one of the most common reasons that you may find empty snail shells in your aquarium as the assassin snail has eaten your mystery snail.

Unfortunately, we have seen some people look at issues with water parameters and parasites in their tank rather than the tank mates resulting in most or all of their mystery snails being eaten.