Cerith Snails: MVP of the clean up crew

Looking to add another little critter to your clean-up-crew (CUC)? Maybe you could pick out a few cerith snails, the next time you head to your local fish store.

Cerith snails are small, snaily scavengers with a pointy spiral shell. They only grow to be about 1 inch long and are well suited for small or large tanks alike.

A popular member of many reef aquarium clean-up crews, this inexpensive reef invertebrate shares space with reef tanks all over the world.

These snails are also known to be hardy and generally ship easily.

cerith snails in bag

Ideal habitat

Cerith snails naturally occur in most oceans worldwide, especially in the tropical Indo-Pacific (Kenya, Red Sea, Mozambique, Madagascar, Western India and Tanzania). Still, most of the specimens traded for aquariums come from the Caribbean.

Out in mother nature, they tend to prefer shallow waters near the low-tide line and would constantly crawl through the sediment deposits in search of food. Their favorite substrates are seagrass meadows, mudflats, and mangrove forest edges.

Ideally, their tank would have a sand substrate and a lot of live rock to provide food and hiding places.
Even though they are generally considered to be pretty hardy, it would be best to avoid major, dramatic swings in water parameters or an unhealthily high concentration of nitrate.

Thanks to their small size, Cerith snails are suitable for nano tanks or larger. If you do have a nano, small or new tank, you might want to be sure to watch and make sure they have enough food to eat and add some additional food to the aquarium if you think there is a risk of starving.

What do Cerith snails eat?

These snails are scavengers. They will crawl through your tank looking to make a nice meal of any detritus, food waste, fish waste, and algae. When you compare that with nassarius snails—that makes them much more valuable members of the cleanup crew.

In a large, established tank, with a sufficiently low density of clean-up crew members, you may not need to do anything special to feed your Cerith snails.

However, you do want to avoid over-crowding, as this can lead to starvation. In fact, many aquarium owners have too many invertebrates in their clean-up-crews (CUCs).

To make sure your inverts have enough food to forage, keep less than one for every 10-gallons of aquarium water volume—and reduce even further than that depending on what other invertebrates you have in your tank.

cerith snail on container wall

Cerith snail behavior

In addition to providing an interesting visual addition to your aquarium, Cerith snails are also functional, because they will move around your tank and scavenge any uneaten food. When they’re not eating, they may bury themselves in the sand. That’s fun to watch and also functional. Stirring up the sand bed tends to be useful, so you don’t develop dead spots.

They are active nibblers and are in constant motion for food, but you might find that they are most active after lights out—so be sure to check back on them after lights-out to enjoy your new purchase.

If you are lucky, you may even get to see the lay eggs on the aquarium glass—so cool.

Can Cerith snails right themselves?

Yes, Cerith snails can generally right themselves unless there is some unusual obstacle.

Cerith snail compatibility

Cerith Snails are peaceful cleaners that won’t disturb or attack any other tank mate. Their small size makes them advantageous when compared with some other larger members of the clean-up-crew because they are able to crawl into tight spaces, as well as in and around frags without knocking them over.

These snails will technically get along fine with your other aquarium inhabitants, but that doesn’t mean that every other fish/invert will get along with them.

Lots of fish and invertebrates enjoy a nice escargot meal. So don’t keep ceriths with anything that would snack on them—that means avoid triggerfish, dog faced puffer fish, hawkfishes, etc.

You will also want to be careful if you have hermit crabs. As you know, hermit crabs don’t make a hard, protective shell on their own. Instead, they rely on the discarded shells from mollusks.

Occasionally, boisterous hermit crabs evict snails from their shells. If you plan to keep hermit crabs and cerith snails together, make sure your crabs are well-fed and have multiple, suitable shells available to switch into. You want to make it very, very easy for the hermits to chose an unoccupied shell.

cerith snail in hand
Notice how small they really are

Are Cerith snails reef safe?

Yes, they are reef safe and are one of they are one of the most effective species you can add to your tank to help keep things clean.

How many Cerith snails do you need?

Please keep in mind that most of the ‘rules of thumb’ with respect to how many snails you need per gallon of aquarium volume tend to be over-estimates and many invertebrates starve and die as a result. It is best to start out with just a few, and add more if you see more need.

Pros and Cons of Cerith snails

With so many good reasons to add a few Cerith Snails to your tank, these mollusks are a great choice to join your clean up crew. Here’s a quick recap of the pros and cons:


  • They are hardy and easy to keep—one of the hardiest snails in a typical reef tank
  • Peaceful, reef-safe and won’t harm any tank mate.
  • Great at cleaning up your tank—they eat detritus AND algae
  • They burrow in the sand substrate, stirring it and help aerate it.


  • The only con I can think of is this—I’m always a bit disappointed at how thoroughly clean up crew members like the cerith snail clean up. They won’t do your job for you, the will just reduce the cleaning a bit.
  • Buyer beware, they won’t replace the work and maintenance you have to do—they just add a level of interest and natural cleanup, but they won’t keep things immaculately clean.
    • What do you expect? They are snails.

Want to see them in action?

Check out this video for more information about Cerith snails:

All About The Cerith Snail

Read this next

Now that you have learned all about the Cerith snail: what they eat, whether they are reef safe, and other important facts, check out this definitive guide:

How to set up a saltwater aquarium


Learn more about these other members of the clean-up-crew:

Your turn

What do you think about the cerith snail? How many do you have in your tank?





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