While they aren’t especially attractive at first glance, there are few snails more popular among marine hobbyists than the tiny, unobtrusive Cerith Snail! These little guys perform several tasks that help keep your tank healthy and clean. For starters, they are first class algae eaters that eat almost every type, even the problematic brown and blue-green strains.
Cerith Snails also help keep your sand bed clean and prevent ammonia from building up by eating leftover food! You’ll still need to do water changes but you can thank your Cerith Snails for making maintenance a little easier for you!
What are Cerith Snails?
There are quite a few snails in the marine hobby worth adding to your tank. They range from the large and attractive Cowries to the tiny but prolific Nassarius Snails. Cerith Snails are another option for fish only and reef tanks for aquarists that need algae and detritus control ASAP.
The Cerith Snail species most commonly found in the hobby come from the Caribbean region. Since they are found in the shallower regions of these tropical waters they thrive in especially warm temperatures. Tidal flats, mangrove swamps, and seagrass meadows are a few of the shallow water environments where Cerith Snails thrive.
But Cerithium sp. are also found in the Mediterranean, East Africa, and as far as the Pacific Ocean. You’re most likely to encounter Cerithium litteratum but if you buy your Ceriths as part of a mixed Saltwater Clean Up Crew you could get any one of dozens of species.
As small as they are, you’ll need quite a few for a sizable algae infestation. Fortunately, Cerith Snails are quite inexpensive and available at nearly any marine aquarium store!
- Common Names: Cerith Snail, Creeper Snail
- Scientific Name: Cerithium sp.
- Origin: Caribbean & Mexican Pacific coast
- Length: 1 inch
- Aquarium Size: Any
- Temperament: Very Peaceful
- Ease of Care: Very Easy
Caring for Cerith Snails
Here are some important care tips for keeping Cerith snails:
Aquarium SIze
Cerith Snails remain very small, rarely growing beyond 1 inch in length. You might come across an exceptional 1½ inch snail. But given their tiny bioload, you can add quite a few to a tank and they will readily disappear into the live rocks and substrate.
One or two Cerith Snails per gallon is an ideal number. If you already have other algae eaters or detritivores then add no more than one Cerith Snail per gallon in order to ensure everyone has something to eat.
Even nano and pico reef tanks can benefit from a small fleet of Cerith Snails chowing down on algae and leftover food, preventing it from rotting and adding to nitrogenous waste issues!
Water Conditions
Cerith Snails thrive in the majority of conditions provided for fish and invertebrates but there is a catch. When adding Cerith Snails to your tank, you should be careful to acclimate them slowly. I recommend drip acclimation because this stage is where Cerith Snails are most vulnerable.
While they are exceptionally hardy once settled into your tank, sudden shifts in water parameters are deadly for them. Salinity, nitrogenous wastes, dissolved minerals, and other parameters need to be adjusted slowly for them, hence the drip.
Once settled, you should have no problems keeping them healthy and happy. Cerith Snails do prefer slightly warmer temperatures because they are found in the shallow, sunlit waters of tropical regions. 74-80℉ is an ideal temperature range for them as is a salinity of 1.023-1.025.
Like all mollusks Cerith Snails are sensitive to buildups of nitrogenous waste products. Ammonia and nitrite should be as close to 0 ppm as possible and nitrate levels of over 20 ppm are dangerous for them. So long as your tank is properly cycled and your biological filtration system is healthy your parameters should be suitable for them!
Are Cerith Snails Reef Safe?
Cerith Snails are entirely reef safe! They don’t feed on corals, sponges, anemones, feather duster worms, or any other sort of sessile invertebrate. They are detritus and algae eaters. Cerith Snails are also too small to knock over coral frags or bother sensitive coral species, making them ideal for grazing in those hard to reach places on your live rock. This makes them better alternatives to Trochus Snails and other larger species that tend to bumble about.
Not only are they reef safe; you might even consider Cerith Snails to be reef essential. By consuming leftover organic matter they prevent the buildup of ammonia and other toxic compounds by consuming it and releasing much less nutrient-rich fecal matter.
Feeding Cerith Snails
Like most marine snails Cerith Snails are classified as predominantly detritivores. This means that they feed on any leftover organic matter that they come across. Uneaten fish food, fish poop, animal carcasses, shed coral mucus…It’s all a buffet to them!
Cerith Snails are also ravenous algae eaters, feeding on green hair, tuft, slime, and other forms of algae. They are also some of the few animals that will eat diatomaceous (brown) and blue-green algae (cyanobacteria), which are typically too noxious for most algae eaters. Unfortunately, even Cerith Snails won’t touch Bryopsis.
Cerith Snails also help turn over the substrate, preventing thick sand beds from going anoxic. In fact, sand or mud beds are essential for Cerith Snails because they do a lot of burrowing when looking for food. The substrate will always provide for them once the algae runs out on the glass and live rock. Cerith Snails tend to be nocturnal anyway, so giving them a place to retreat when the lights are on reduces stress for them!
Cerith Snails are best added to mature aquariums or aquariums with live sand beds in place. In either case, you’ll have healthy colonies of microorganisms like bacteria, diatoms, algae, and invertebrates that all provide food for sand sifting organisms like Brittle Starfish and Cerith Snails.
Another reason to use live sand is because it quick-starts your cycling process. Since the nitrifying bacteria are already alive and thriving in the sand, you can get up to full fish and invertebrate carrying capacity that much faster!
Many marine tanks have a refugium running in place of a protein skimmer to export nutrients. Refugiums use the relationships between animals and plants as it works in Nature to soak up nutrients like phosphorus and nitrate rather than relying solely on technology! Cerith Snails are great additions to a refugium, helping to process organic matter and keeping it from re-entering your ecosystem.
If you grow marine macroalgae like caulerpa or chaetomorpha in your refugium, you can also add handfuls to your tank on occasion to feed your algae eating Cerith Snails if the greens start to run out in the main tank!
Tank Mates for Cerith Snails
Cerith Snails are entirely peaceful and get along with any animal that won’t eat them. They are harmless detritivores and algae eaters and can be kept with soft corals, LPS corals, and SPS corals of all kinds, Giant Clams, and other sessile invertebrates.They also get along well with shrimp and other marine invertebrates.
The only ones you do need to watch out for when keeping Cerith Snails are crabs. Nearly all crabs are opportunists that will eat anything they can overpower. Emerald Crabs, being algae eaters themselves, tend to be quite safe with Cerith Snails so long as the algae doesn’t run out.
Unfortunately, Arrow Crabs and other medium or larger species will gladly pluck a meaty snail right out of its shell. Most reef safe hermit crabs are detritivores themselves and too small to be a threat to a Cerith Snail. But occasionally hermit crabs are known to forcefully eject a snail if they can’t find a shell.
Fish are great tank mates so long as they aren’t specialist mollusk eaters. This means no Triggerfish, Pufferfish, Snowflake Moray Eels, medium to large Wrasses (dwarf wrasses can work), and other lovers of crunchy animals.
When keeping Cerith Snails with other lovers of algae and biofilm, you may run out of food for both. In this case, you’ll have to regularly supplementally offer vegetables for Tangs, Angelfish, Foxface Rabbitfish, and other mostly vegetarian fish. Strips of macro algae or dried Japanese seaweed (Nori) clipped into place are perfect for both your fish and your Cerith Snails, which will vacuum up any leftovers!
Good Tank Mates for Cerith Snails:
- Most Marine FIsh
- Soft Corals, LPS Corals, SPS Corals, Sponges, Giant Clams, Feather Duster Worms, and other Sessile Invertebrates
- Starfish, Shrimp, and other Invertebrates
Poor Tank Mates for Cerith Snails:
- Triggerfish, Pufferfish, Wrasses, Snowflake Moray Eels, and other Invertebrate-Eaters
- Arrow Crabs and other Predatory Crabs
Breeding Cerith Snails
As simple as Cerith Snails are to care for, you’d think breeding them would be a piece of cake! However, they rarely get out of control (unlike Ramshorn and other freshwater snails) because Cerith Snails rely on certain unknown triggers to begin spawning.
Since Cerith Snails are known to be extremely sensitive to changes in salinity and other water parameters, it’s thought that they may rely on seasonal variations in temperature and salinity to spawn. Many aquarists will find that their Cerith Snails will suddenly spawn en masse, depositing long strings of eggs on any hard surface including the aquarium glass.
Some snail eggs are encased in a hard coating or bitter jelly that discourages predators. But Cerith Snails are more or less unprotected, which means that your fish and invertebrates will likely gobble them up before they ever hatch.
Even when kept in peaceful environments Cerith Snail larvae rarely, if ever, reach adulthood. Many snails that live in similar environments, such as Nerite Snails, are actually migratory. Cerith Snail young may need brackish or even freshwater to mature before returning to the ocean, making rearing them next to impossible.
Fortunately, they are so abundant in the wild that you can get as many as you need at an affordable rate! Your Cerith Snails may not reproduce but they will eat up nuisance algae, turn over your sand bed, and continue to improve your marine aquarium for years to come!
