How Many Assassin Snails Should You Get?

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Assassin snails are renowned for their predilection for snail meat. They are considered to be pest controllers thanks to their ability to kill and consume all snails plaguing your tank with unparalleled efficiency. But how many do you actually need?

While assassin snails are typically peaceful and docile, they can enter conflicts with other bottom feeders over territorial and food disputes. They may also become prey to some species of fish, especially if there are many of them lurking around.

The ideal range would be between 2 and 4, depending on your tank’s size.

Can You Get Just One Assassin Snail?

Yes, you can keep one assassin snail in the tank, provided that the tank is small enough. The problem is that assassin snails are only useful when it comes to handling a snail invasion in your tank. And you’re unlikely to experience any meaningful snail invasion in a 5-10-gallon tank. Not one that you couldn’t handle by yourself with relative ease anyway.

When it comes to a 20-30+ gallon tank, things change a bit. This time, the habitat is larger, allowing snails more room to cover. This will make them more difficult to remove, especially if the tank’s layout involves a variety of plants and decorations that the snails could use for cover.

One assassin snail won’t make much of a difference in such a habitat. Sure, it will hunt the snails down, but it won’t be nearly as effective as you would like. And your goal is to stop the snail invasion in its tracks, which means you need more than one assassin snail for the job.

How Many Snails Will Assassin Snail Eat Per Day?

Assassin snails have a pretty hefty appetite, so they will consume around 1-2 snails per day, depending on the prey’s size. It’s safe to say that a group of 5-6 assassin snails will quickly eradicate your snail infestation in a matter of days, based on how large the tank is. They won’t cover the ground too fast, but they’re constantly on the move, especially when hungry.

They’re also effective eaters because assassin snails, while not social in nature, will often gather to share the same prey. So, they’re fast about it.

As an important note, assassin snails make for quite pleasant tank inhabitants. They won’t interact violently with other tankmates unless there’s a conflict of food interest at play. So, if you plan on keeping your assassin snails for a long time, you should consider feeding them extra. Especially if the supply of available pest snails is diminishing.

Assassin snails are omnivorous, so they need a varied diet to remain healthy. Assassins will consume a variety of foods, like protein pellets, brine shrimp meat, snails, algae and plant matter (preferably dead), a variety of worms, and even feeder fish. You don’t need to supplement their diet if you’re dealing with a massive snail invasion.

This will incentivize your assassins to hunt and feed on the existent snail population. But once the tank is clean, they need additional sustenance to remain healthy. A good, healthy, and thriving population of assassin snails will keep your tank clean of any pests moving forward. Also, assassin snails aren’t excellent breeders, so you don’t need to worry about them taking over the tank.

How Long it Takes for Assassin Snails to Clean Up Pest Snails?

It shouldn’t take more than a few days for a group of 4-6 assassin snails to eliminate all pest snails in your tank. Clearly, this is only a general timeframe since the actual time necessary to achieve that differs from case to case.

Your assassins’ effectiveness depends on the tank’s size, how many pest snails there are, and the tank’s layout. If you have a heavily planted and decorated tank, your assassins will work harder for their meals.

But, generally, a tight group of assassin snails should get the job done in approximately a week, if not sooner.

Do Assassin Snails Eat Each Other?

No, assassin snails will not eat each other. They can recognize their own, so cannibalism is unlikely to happen. That being said, it can occur in extreme cases when snails have to choose between eating their brethren or starving to death. Fortunately, this is an unlikely scenario in a well-maintained environment where snails have sufficient food at their disposal.

Can Assassin Snails Eat Snail Eggs?

Yes, assassin snails will also consume snail eggs, if any are available. These are opportunistic eaters, so they won’t back down from consuming anything nutritious around their habitat. This makes them ideal as pest controllers in snail-infested aquariums, given that many snail species are excellent breeders.

Just make sure you have sufficient assassin snails for the job. As a general rule, go for 2 snails for each 5 gallons of water. This should be enough to improve their killing effectiveness because assassin snails are slow movers. So, they need time to get the job done. The more of them there are, the more effective they will be at their job.

Even better, assassin snails won’t mind the presence of others of their kind. They’re not particularly aggressive or territorial and will mostly share their meals than compete over time. This makes them an awesome addition to your tank, even in higher numbers, so long as you don’t overpopulate the habitat.

Can Assassin Snails Breed in a Planted Tank?

Yes, assassin snails will breed in a planted tank, or any tank for that matter. What matters is for them to be housed in a calm, healthy, and clean environment with sufficient food and adequate temperature. The environmental temperature needs to sit between 75 and 80 F. Apparently, female snails stop laying eggs if the temperature drops below 65 F.

If you’re looking to breed your assassin snails, consider increasing their numbers to at least 6. The core problem here is that it’s difficult to sex the snails. The differences between males and females are mostly non-existent. Increasing their numbers will statistically increase the likelihood of getting both males and females into the mix.

The mating and breeding process is relatively straightforward. After mating, the female will lay the eggs individually on the substrate. Unlike other species, assassin snails don’t need a certain layout to spawn. The resulting snail babies will immediately bury themselves in the substrate to find shelter and protection from predators. They will mostly feed on the existent bacterial cultures in the substrate and will come out once they’ve matured. This generally takes place 6 months later.

Assassin snails are more difficult to breed for the most part, primarily due to the difficulty of sexing them. They also don’t spawn too many eggs. To compensate for that, assassin snails are always in the mood for mating. So, they typically produce eggs at a steady pace. These require approximately one month to hatch in the ideal conditions.


Assassin snails are probably the most effective snail hunters you can get. They move slowly and like to take their time to get the job done. But they’re quite effective at it and will often combine their efforts to overwhelm and consume their prey faster.

Keep an eye on their population, feed them extra if they require it, and enjoy their presence while they last. Assassin snails can live up to 2 or even 3 years in optimal conditions.

I also recommend breeding them since their presence is the best deterrent against any future pest-snail invasion.

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.
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