Black Devil Snail: More Angelic Than the Name

black devil snail

The black sea devil is also known by the scientific name Faunus ater. Although these snails sound like something out of a rock song, they’re actually not as frightening as they sound. Some might argue that they look a little devilish, but they certainly don’t act that way.

In fact, this might be one of the least problematic snails out there!

Let’s take a deep dive into the watery world of the black devil snail, shall we?

What Are Black Devil Snails?

Despite this snail being a great and interesting addition to any home aquarium, not very many people have heard of it, and even fewer have added it to their tanks. In fact, not even gastropod experts and scientists know very much about it.

As well as black devil and faunus ater, this aquatic snail is also known by a host of other names, including:

  • Spike snail
  • Lava snail (not to be confused with volcano snail)
  • Black devil spike snail
  • Black spike snail
  • Cappuccino snail (possibly the same snail, debates ongoing)

These are peaceful and water snails, but they’re not that fussy about where they live. They’re also very adaptable, super hardy, and quite odd to look at. In fact, if you were to take a quick glance, you might not even realize you were looking at a snail at all.

These are common in the aquarium world, but they deserve to be! They would make a great addition to your cleanup crew, and they look pretty neat to boot.

What Do Black Devil Snails Look Like?

These hardy snails actually look more like insect larvae or pupae than snails, but that could just be a clever defense strategy against predators. Cone-like and elongated in shape, they look more like cone or Cuban painted snails than rounded garden snails.

The color of the shell, which is actually a periostracum rather than a conventional shell, is dark, usually very dark brown or black. It will sometimes have brown coloration (hence ‘cappuccino snail’.

The spire-tip is often lighter in color and broken off. The area around the opening of the shell is also usually a lighter shade, too. The shell itself has around 20 whorls, and the body can range in color from light or dark brown to black, red, and gray.

How Big Do Black Devil Snails Get?

This shell can reach some serious height… or length, depending on which way you look at things.

The average black devil shell length tends to sit between 2 to 2.5-inches (5 to 6 cm), but they can reach lengths of 3.5-inches (9 cm).

Is the Black Devil Snail a Freshwater or Seawater Snail?

This snail is technically neither of those things. If you want to get really specific about things, black devil snails are a brackish water gastropod, living in a mix of salty and fresh. If you had to pick between fresh and salt water for an aquarium setting, fresh water would be best.

Where Do Black Devil Snails Come From?

This species comes from and is found in the Pacific. They have been noted in the ‘wild‘ in northern Australia, India, Solomon and W/S Pacific Islands, Sri Lanka, Thailand, Indonesia, China, and more.

Habitats include brackish waters — the mouths of rivers and streams, in estuaries, intertidal spots, mangroves, ditches, and lagoons.

What Do Black Devils Eat?

This species is a grazing, omnivorous one. It’ll eat plants, animals, and other organisms, such as algae. In fact, the algae-eating behavior might just be the reason you decide to add one or more of these gastropods to your aquarium.

As well as cleaning your tank of algae, black devil snails also eat:

  • Some live plants
  • Dead and decomposing plant matter
  • Fish food leftovers
  • Shrimp food

In an aquarium setting you will likely feed these snails other foods. Fresh vegetables plus fish or shrimp food works for this. You will also need to add a form of calcium, such as cuttlefish.

Can You Have Black Devil Snails as Pets?

Yes, you absolutely can have black devil snails as pets. They’re super easy to care for. Surprisingly, though, they aren’t all that popular in the aquarium or exotic/alternative pet industry.

Black Devil Snail Care

There are many benefits to have black devils in your freshwater janitorial team. There’s no chance of a population boom, they’ll eat all the organic material you’ll otherwise need to clean out yourself, and they look pretty interesting.


Ideally, you’ll want at least a 10-gallon (38l L) tank for this species. They are quite active and like to move around, and it’s noted that they’re quite fast-moving sometimes. You should add on 5-gallons for a second and every subsequent snail.


The habitat will need some substrate. Although not a full-time burrower, black devils do like to hide themselves away by burrowing down from time to time, and they enjoy sifting through it. You could use gravel for this, but the stones and possibly sharp edges might damage the somewhat delicate shell. This species is known for having quite tough and durable shells, however.

Another substrate you could consider is sand, or a sand-gravel mix. This is the kind of substrate they would have in their brackish natural habitats.


When it comes to plants, these snails are omnivorous, which means they’ll eat plant material and animal matter alike. They could and likely will have a little nibble on your plants. For that reason, ensure you don’t put plants in the tank that you’d be sad to lose. You might need to replace them from time to time, which can be costly.

Hiding Spots

Black devils, like most snails, like a couple of hiding spots, so rocks, plants, and other decorations (driftwood, for example) are recommended.

Water Parameters

Although hardy, you will need to ensure that you are mimicking a habitat that the snail would naturally (and therefore be happy to) live in.

Water pH: 7 to 8.5

Water temperature: 70 to 77 F (21 to 25 C)

This snail is generally incorporated into brackish or freshwater aquariums, but some owners have reported keeping them in full saltwater environments with no issues. If you choose to add this species to a marine tank, be aware that there might be some repercussions.

How Many Black Devil Snails Should You Have in a Tank?

You can have a solo black devil in your tank, but it might be nice to give that lonely gastropod a friend. Unless your tank contains brackish water, they won’t reproduce, so you won’t be overloaded.

Two black devils mean more algae-eating, too!

Black Devil Snail Breeding: Easy or Hard?

If you have black devils in a freshwater tank setting, they will never reproduce. The species requires slightly salty brackish water.

Not very much is known about the breeding process of this aquatic snail, but we do know that they lay eggs, need brackish water, and have very little involvement with juveniles past the laying point.

Where Can I Buy Black Devil Snails?

It is worth trying in local and online aquarium stores but this snail isn’t all that readily available. For reasons I don’t personally understand, this gastropod doesn’t seem to be all that popular.

Amazon is another great place to look, although always do due diligence when it comes to buy live creatures (or anything) online. Use a reputable store, read the reviews, and make sure you read the full description of whatever you’re buying.


Is Faunus Ater Edible?

Yes, it is edible, but eating black devils seems to feature mostly in Thai and Filipino cuisine.

Black Devil Snail vs Rabbit Snail: What’s the Difference?

These two snails definitely look alike, but they aren’t the same. They don’t even come from the same families. There’s no relation between the two, so there’s no chance of them coming together to create rabbit-black devil hybrids.

No, they’re not related at all. The two species come from completely different gastropod families. They cannot interbreed.

You May Also Like