Hermit crabs are often thought of as short-lived little critters that you get when you visit the beach. In reality, though these pets can live for decades with the right care. Here we will let you know how to care for your hermit crab so it will live a long healthy, happy life.
Unfortunately, the hermit crabs that are sold in these kitschy tourist shops are completely mistreated and set up all wrong. They are housed in cheap metal cages which are toxic to them, they are way overcrowded and don’t have proper humidity, heat, food, or water.
To top it all off, the sales clerks are misinformed in how to properly care for them, and hand off the wrong information. It isn’t their fault because they aren’t trained in hermit crab care. All of this leads to the hermit crab perishing in a few weeks or even days.
Table of Contents
Hermit Crab Information
There are nearly 1,000 different types of hermit crabs, but only a select few can be kept as pets. The others are either endangered or simply don’t handle captivity because they need such specific needs met.
You may find hermit crabs along the shore when you are at the beach. While they may be crawling on land, they may be a marine hermit crab, or vice versa. You shouldn’t take a hermit crab from its natural environment as a pet.
Most wild hermit crabs need such specific requirements, temperatures, water dynamics, and more that it’s just not feasible to keep one healthy. When looking for one as a pet, be sure to find a reputable hermit crab keeper. You may even be able to adopt one that the previous owner could no longer care for.
There are marine and terrestrial hermit crabs, and here we will go over the land hermit crabs. The two most popular species are Caribbean and Ecuadorian hermit crabs.
Caribbean Hermit Crab
- Experience Level: Beginner
- Family: Coenobitidae
- Scientific Name: Coenobita clypeatus
- Other Names: Purple pincher, Tree crab
- Adult Size: 2 to 6 inches
- Lifespan: 3 to 12 years average
- Average Price Range: $5 to $40
Ecuadorian Hermit Crab
- Experience Level: Intermediate
- Family: Coenobitidae
- Scientific Name: Coenobita compressus
- Other Names: Pacific hermit crab, Eccie
- Adult Size: 1 to 2 inches
- Lifespan: 3 to 20 years average
- Average Price Range: $9 to $15
Interesting Facts About Hermit Crabs
Hermit crabs are not considered true crabs. This is because their abdomen does not produce a hard exoskeleton and is soft and vulnerable. This is why they carry along discarded and empty shells.
When hermit crabs molt and grow, they often bury themselves in the sand while the soft shell is hardening, then they have to find a larger shell to accommodate the new growth.
All hermit crabs have gills. Yes! Even land-dwelling hermit crabs have gills, they have to keep them moist so they can breathe. That’s why they need a very humid environment, which we will get into later.
Hermit crabs are omnivores and scavengers. These little crabs do a great job of getting rid of detritus and discarded food, and they help to clean rotting carcasses. Some hermit crabs even eat feces, such as fish, turtle, and mammal poop!
In certain parts of the world, some hermit crabs are so good at getting rid of dead fish and other carrion, there are actually fewer flies around. The hermit crabs clean out the rotting flesh that these flies need in order to lay their eggs, which helps to reduce the population.
Physical Characteristics Of Hermit Crabs
Some hermit crabs grow to over 3 feet in length while others will never grow more than half an inch. They come in a wide array of colors and habitats, but they mostly have a few things in common.
Like true crabs, hermits have eyestalks. Some are long, some are short, and the eyes can be oval, round, or comma-shaped.
They have 5 pairs of legs but only use three for walking. The other two pairs of legs are so small they are left inside the shell.
The Natural Habitat
Hermit crabs live mostly around and in tropical habitats.
They need access to fresh and saltwater with warm temperatures and a humid environment. Some stick close to the coast, while others live in marshes, forests, or wetlands.
They can come from Asia, Australia, the Caribbean, Indonesia, and the African coast. There are even some species that live off the coast of Hawaii.
Hermit Crabs Have A Long Life
In the wild, hermit crabs can live for 30 to 40 years. While many animals tend to live longer in captivity because they are cared for better, and don’t have to search for food or fight away predators, the hermit crab is different.
In captivity, hermit crabs don’t usually live for more than a few months. When they receive the right care and the correct environment though, they can become beloved pets that live for a few decades.
How Do Hermit Crabs Reproduce?
Even when conditions are optimum in a hermit crab enclosure, or “crabitat” as it’s often affectionately called, these animals very rarely mate. Not much is known about their mating habits because these little crabs are often nocturnal.
Females also hide the eggs inside their shells until they are ready to hatch. She then goes to the ocean, releases them in the surf, and returns to her normal routine.
In captivity, if—and that’s a big IF—you see the tiny eggs you’ve done what very few hermit crab owners have ever done. Don’t celebrate too quickly because eggs probably won’t hatch unless you have a great ocean-like set up to keep them alive.
Depending on the size of the crab, a female can lay between a few thousand eggs to 50,000 at a time. The tiny, red or grey eggs cluster together until they hatch microscopic, aquatic hermit crab babies called zoea.
Animals That Feast On Hermit Crabs
Hermit crabs have a few defense mechanisms, but there are still plenty of predators that have figured out how to make a meal of these crustaceans. Predators of hermit crabs include:
- Seagulls and other shorebirds
- Fish such as pufferfish, sheepshead, triggerfish, and more
- Bigger crabs and even other hermit crabs
Can You Legally Own Hermit Crabs?
In most states, it is legal to own hermit crabs, but in many places, it is illegal to take them from the wild. As we mentioned above, it’s really not a good idea to take them from the wild in the first place.
Just be sure to check your local area to make sure it’s legal to own hermit crabs. Laws about owning certain pets can change without you knowing it.
Where Can You Get A Hermit Crab?
You should avoid beachside hermit crabs because they are rarely taken care of.
They are thrown into large communities without proper water and food. Before that, the hermit crabs are pulled from their own shells and put into toxic painted shells to make them look prettier.
Painted shells are dangerous for hermit crabs because they may try to eat the paint that inevitably chips off. This can harm the hermit crab, or prove fatal for them.
You can find hermit crabs in pet stores. These may be cared for a little better, but your best bet is to find an adoption agency if one is in your area or find a licensed pet distributor such as the Nature Gift Store.
You’ll Need A Proper Hermit Crab Habitat
When you get a hermit crab, or before you purchase one you’ll need to make sure you have everything it needs for proper health and a long life.
The first thing you need will be a tank. You’ll need a 10-gallon aquarium tank of glass or acrylic at a bare minimum.
If you plan on housing multiple hermit crabs you’ll need a larger tank. A 20-gallon will suffice for 2 or 3 small hermit crabs. Figure about 10 gallons per hermit crab.
Hermit crabs can be social if they have enough space. When they don’t have enough room to move around on their own, they can become aggressive with each other and may eat smaller hermit crabs.
Since these little crabs come from tropical regions they need warm temperatures. You’ll need to get a heating pad that you can attach to the back side of the crabitat. There needs to be a temperature gradient inside.
The warm side of the tank needs to be around 85℉, while the cool side doesn’t need to get lower than 75℉. This is just a general temperature, but some species may need it warmer or cooler for optimal health.
Use Fluker’s Premium Heat Mat for Hermit Crabs, 6″x8″ to help provide heat for your hermit crab.
Next, you need a proper light and a timer. The light needs to be either a fluorescent or LED bulb that does not produce heat. Heat lamps produce too much heat and can quickly dehydrate your crab.
If your room is naturally lit and provides 12 hours of sunlight you won’t need a light source. Just be sure you don’t place the tank directly under or in a window. The sunlight and heat are intensified as it passes through the window glass, and can harm your hermit crab.
For most households, a timer set for 12 hours on and 12 off with a non-heated lamp is the best choice.
Hermit Crabs Need Humidity
Hermit crabs have gills, even the land dwellers we are talking about here.
In order to breathe sufficiently, they need a lot of humidity. They will often carry water in their shells to help moisten their gills when they need to, but keeping the humidity level high is the best way to keep them from suffocating.
Hermit crabs need a constant humidity of around 70%. You’ll need a hygrometer to make sure the crabitat meets that requirement. Daily misting and the proper substrate are ways to make sure you have the proper humidity.
The best way to measure the temperature and humidity is to use this REPTI ZOO Terrarium Thermometer Hygrometer.
Hermit Crabs Need Freshwater And Saltwater
You need to provide daily sources of clean fresh and saltwater for your hermit crab. They need fresh water to drink and moisten their gills, and they need salt water to keep in their shells.
The saltwater is utilized to balance alkalinity, minerals, and electrolytes in the hermit crab. It’s also used to keep the shell attached to their soft abdomen.
You’ll need to use spring water, or distilled water as tap water contains too many harmful substances. Chlorine and other chemicals are toxic to hermit crabs. It only takes a tiny amount to be fatal as these crabs are so small.
What wouldn’t affect us at all, can mean mortal peril for tiny hermit crabs.
The same goes for the saltwater. You can’t mix table salt or any salt that you use to season food, instead, you’ll need marine salt from pet stores or a pet/aquarium supplier.
The water needs to be deep enough for your hermit crabs to submerge themselves in. The hermit crab needs to be able to climb out easily as well, as they can drown if they can’t get out of the water.
Proper Water Dishes
The best kind of water dish is not made of any kind of metal. Most metals are toxic to hermit crabs, especially copper, iron, and lead. If you use smooth plastic, you may need to add small rocks or gravel so your hermit can easily climb out.
Water dishes with textured bottoms that are deeper on one end are the best. It allows room for your hermit to submerge itself, but also will let it climb out easily.
Just be sure to clean out and replace the water daily. Since they are typically nocturnal, hermit crabs will usually submerge themselves at night to replenish their shell water. Stagnant, dirty water isn’t good for them.
Here is a great water dish with graduated steps that your hermit crab can crawl out of, Fluker’s Lagoon for Hermit Crabs, Water Bowl with Steps.
Hermit Crabs Need Plenty Of Substrate
One way to help keep the humidity at the proper levels is by using the correct substrate. You can use sand, soil, or a substrate mixture. The best substrate is a 5-part-to-1-part mixture of all-purpose sand and coconut coir.
All-purpose sand is one of the best kinds you can get. It’s clean, small enough to not be a problem, and it holds moisture well.
The substrate needs to be damp enough to pack it. Think of the damp sand you make sandcastles with at the beach, it needs to be that consistency. Your hermit crab needs to be able to burrow, and the tunnel needs to hold its shape.
Play sand may not be that great for your hermit crab. It’s very fine, doesn’t hold moisture very well, and many brands now treat the sand with antibacterial or antifungal chemicals that can harm your hermit crab.
Calcium sand should never be used. When this sand gets moist it hardens and tends to clump together, which causes it to stick to your hermit crab after it molts. The sand then gets into the shell and can cause irritation or sores.
It’s sold in pet stores so you’d think calcium sand is safe, but it’s really best avoided. Instead, use aquarium or marine sand.
You can also use a soil mix, but just make sure it doesn’t have any fertilizer or additives.
Hermit Crabs Like To Burrow
When you’ve picked out the substrate you want to use, you need to pack it in.
Hermit crabs like to burrow so you’ll have to layer it in pretty deep. A good rule of thumb is to go 3 to 4 times as deep as your hermit crab’s shell.
Hermit crabs have to molt occasionally. When they feel this beginning to happen, they will burrow into the substrate for safety from predators. There they shed their exoskeleton and will remain there until the outer shell hardens again.
This process can take a few weeks to a few months. While they are hidden away they will eat their old exoskeleton, and then return to the light when the process is complete.
If you start to smell something really bad in the enclosure, then the crab has probably expired in the burrow and needs to be removed.
Otherwise, just leave the hermit crab alone. Digging it out, or bothering it while it’s molting can stress it so bad that the hermit crab dies.
Leave your molting crab alone until it comes back out of the tunnel and starts acting normally again.
Add In Some Crabby Accessories
Aside from food and water dishes, your hermit crab needs a few hiding places and things to climb on.
The tank also needs a tight-fitting lid. Hermit crabs are curious explorers and can escape their tanks.
Be sure to put a few huts your hermit crab can hide in. They tend to be nocturnal and may hide away during the day.
You also want to put in things they can climb on. Most hermit crabs live on or near trees, especially mangrove trees. Cholla wood, rope hammocks, or other climbing accessories are a necessity to keep your hermit happy.
Here is a bendable climbing stick your hermit crab will enjoy, Hermit Crab Climbing Toys.
An assortment of shells is essential as well, especially if you have more than one hermit crab in the crabitat. When resources are scarce, larger hermit crabs can forcibly evict smaller ones from their shells.
Make sure you have several different shells of different sizes for your hermit crabs to test drive.
Plants can also be added to your hermit crab’s home. Artificial plants are great because you don’t have to worry about trimming them if they are toxic or not, and you’ll never have to water them.
You can add live plants if you wish, just be sure they are not toxic if your hermit crab decides to nibble on them. They also need to be able to withstand high humidity, sandy soil, and warm temperatures.
A few live plants that will work with your hermit crab habitat include:
- Air plants
- Spider plants
- Loose leaf lettuce
What Food Is Best For Hermit Crabs?
The best thing you can feed your hermit crabs is a varied diet of fresh vegetables, fruit, and protein. You can feed them commercial hermit crab food, but only as a supplement and it has to be free of preservatives such as ethoxyquin and copper sulfate.
Vegetables such as bell peppers, broccoli, spinach, and leafy greens are great for hermit crabs. You can also feed them fruits on occasion such as apples (no seeds), bananas, and berries.
They need to be fed protein a few days a week too. This can include blood worms (rehydrated freeze-dried cubes are a great option), brine shrimp, sardines (plain), oysters, scallops, fresh fish, chicken, or beef. These can be raw or cooked.
If you’re cooking the protein, don’t add any seasoning at all. Boiled eggs, shells, and all are a great treat and a great way to add extra calcium.
Just cut a small section of the egg with the shell on it and give it to your hermit crab.
Keep The Tank Clean
Hermit crabs only eat a tiny amount at a time, and sometimes they will hide food.
Remove any uneaten food every day, and look and give a sniff to locate any possible hidden food. Leaving old food for too long will introduce bacteria and mold.
Do a spot clean daily for leftover food, and poop. Clean and replenish the water dishes.
Are Hermit Crabs Grouchy And Withdrawn?
You’d think with the name “Hermit” these crabs would be cranky all the time and don’t want any company. Don’t worry, you won’t see them walking around with signs that state “Stay Out Of My Tank!”
Hermit crabs, once they are properly socialized are active and engaging pets. When you first get them they will be skittish and will withdraw into their shell. During this time, just let them get used to you being around.
Don’t reach in and pick them up until they stop retreating whenever you get near the tank. This may take some time so be patient. Once they are used to you, they will crawl around on your hand and explore.
Hermit crabs do have strong claws, but they will very rarely pinch with them. They may accidentally pinch you if they are trying to hold on. They don’t have fingers and can only use their legs or claws to climb and hold on.
To avoid this, hold them by the shell, and keep them on your open palm. Keep your hand close to the ground so if they fall it won’t hurt.
Generally, hermit crabs don’t like to be held, so if you do pick it up, keep the time down to a minimum. But they won’t pinch you out of aggression. Their main defense tactic is to withdraw into their shell.
Do I need to bathe my hermit crab?
A: In the wild, hermit crabs will wash themselves off when they dunk themselves in a pool of water or in the surf.
Some people say giving your hermit crab a bath is beneficial, or even turning it upside down and dunking it in water. I personally think it’s best to let the crab bathe itself.
This allows the crab to take care of itself, reduces stress, and more closely mimics their natural habitat.
Do hermit crabs need a sponge to drink?
A: Sponges can be a pain to clean, they can hold onto bacteria, and they get torn up by your hermit crabs. If you offer fresh water every day in a small, shallow bowl, the hermit crab will drink water from it.
It’s up to you if you provide a sponge for drinking, but they don’t hold water for long and can be a nuisance.
Do hermit crabs need light at night?
A: Hermit crabs need a natural day and night schedule. As long as they get 12 hours of light during the day, they don’t need light at night.
All Finished Up
As you can see, hermit crabs need special care for a long life. It’s not hard to care for a hermit crab, or even to care for a few of them, but special needs should be tended to.
You’ll need a proper substrate and a proper depth for burrowing. You’ll need non-chlorinated fresh and saltwater, plenty of accessories, the proper humidity and temperature, and the correct food.
With all these needs met your hermit crab can live for 20 or even 30 years! We hope this helps you take care of your little Hermie. If you have a comment or if there was something we missed that you’d like to know about, leave us a message below. We love to hear from our readers!