|Type of Enclosure:||Glass aquarium|
|Size:||Minimum of 10 gallons|
|Temperature:||70° - 80°F|
|Humidity:||75% - 90% (relative humidity)|
|Substrate:||Sand or coconut fiber|
Never use a small plastic container to house your hermit crabs. They need plenty of room to climb and move around. The smallest enclosure you should use for two small to medium sized hermit crabs is a 10 gallon aquarium. Housing multiple medium sized hermit crabs or two large hermit crabs can require an aquarium as large as 30 or 40 gallons.
Hermit crabs are good escape artists, so the enclosure will need a secure lid. If your house is humid and warm, you can use a wire mesh lid with latches. However, if there is a chance that the dry air in your home will affect the humidity levels of the habitat, we recommend the use of a glass or Plexiglas lid. You could also use a wire mesh lid with most of the lid covered by plastic wrap.
Though it is important to keep the enclosure warm, never place it on a windowsill or anywhere else that it will be in direct sunlight. This will raise the temperature dangerously high, and you run the risk of actually baking your hermit crabs.
You should choose a substrate that is easy to clean and that will allow your hermit crabs to tunnel and burrow in it. The two preferred substrates are sand and coconut fiber substrate. You can purchase special terrarium sand or play sand. Coconut fiber substrate such as Eco Earth works well also, and is especially good for tunneling and burrowing. Many hermit crab owners elect to use a combination of the two. Crushed coral is also an option for substrate. Avoid gravel, wood chips, or other substrates that are unsafe or do not allow them to dig.
Decorations and Accessories
Hermit crabs love to climb, so they will need plenty of accessories in their cage for entertainment. The following items work well as decorations in a hermit crab enclosure:
In addition to the above accessories, you will also need to place two water dishes in the habitat - one for fresh water and one for saltwater. They should be big enough that your hermit crabs can submerge themselves, but set up in such a way that it is easy for your crab to get in and out of them. The fresh water container should hold spring water or de-chlorinated water. The saltwater container should be a mixture of de-chlorinated or spring water and a special aquarium salt mix (regular table salt is not acceptable). We recommend putting these dishes in a low area of the habitat to mimic a shoreline, as hermit crabs would generally live near the ocean.
You should also place extra shells around the habitat for the hermit crabs to change into. There should be at least three shells per hermit crab, and the shells should be at least as big as or slightly larger than the crab's current shell.
Humidity levels are very important to the survival of hermit crabs. Hermit crabs have modified gills that allow them to breathe, but to be able to breathe, they need to breathe moistened air. Air that is too dry will actually dry out their gills, making it increasingly difficult to breathe until they finally end up suffocating. This is why their habitat needs to have a moist, tropical feel and a relative humidity that is no lower than 70%.
To help keep humidity levels where they need to be, keep the substrate damp, and avoid using substrates that do not retain moisture well. However, the substrate should not be soaking wet, as humidity that is too high can cause health issues as well. We recommend moistening the low and middle areas of substrate while leaving the higher hills dry. You can also mist the entire enclosure daily to provide plenty of moisture in the air.
Another way to maintain humidity levels is to use bubble bowls made from airstones, airline tubing, and air pumps typically used for aquariums. Simply put an airstone in the bowl of water and use the tubing to connect the airstone to the pump. This will cause the water in the bowl to bubble and circulate, increasing humidity as well as helping to keep the water fresh.
Always have a hygrometer in the habitat to monitor humidity levels. Guessing or approximating humidity levels can result in the death of your hermit crab. Be sure to check whether your hygrometer measures relative or actual humidity. Relative humidity levels should be 75% to 90%. Actual humidity levels will be approximately 50% to 60%.
Keeping within your hermit crab's temperature range is equally as important. Temperatures that are too high will cause irreversible heat damage, and improperly low temperatures will alter a hermit crab's metabolism. You may need to use outside heat sources to maintain temperatures within the habitat, especially during colder winter months. Primary heat sources can include under tank heaters and 15 watt reptile heat lamps. The temperature of the habitat should always be monitored with a thermometer.
Many people do not use special lights for their hermit crab's habitat, but lights can be very beneficial, both for providing healthy daylight and for maintaining proper temperature. When choosing lights, pay close attention to wattage. Lights with a high wattage over a small tank will cause the humidity to drop below proper levels as well as raise the temperatures into a dangerous range for your crabs. We recommend the use of a 15 watt bulb for a 10 gallon tank. The bigger the tank, the higher the wattage can be, such as a 60 watt bulb for a 55 gallon tank.
Lights that you can use include fluorescent bulbs that provide UVB and UVA light, incandescent bulbs, nighttime heating lamps, or a combination of these. You should use a timer to make sure that the light cycles are maintained appropriately.
Regular cleaning is necessary to keep your hermit crabs healthy and their environment safe. The following tasks should be part of your cleaning routine:
A Note about Safety
Always set up the enclosure before bringing home your hermit crabs. It is crucial that you stabilize the temperature and humidity levels before putting any crabs in the habitat. The hermit crabs you bring home will already be under stress, and putting them into an enclosure with improper or fluctuating temperatures and humidity levels can cause serious adverse side effects including lethargy, loss of limbs, and even death.
Setting Up the Habitat
Now that you know what should go into the habitat, it's time to learn exactly how to set it up! The following list will give you a step by step guide to setting up your crabitat.
Once the temperature and humidity levels are stable, you can place your hermit crabs in the habitat.
As you can see, properly caring for hermit crabs takes time and effort. Though they are often purchased as pets for children, we recommend that they remain a family pet with the responsibility of day to day care and habitat maintenance falling on a parent.