Hermit crabs are a very popular pet because they are personable, yet easy to care for. Still, there are a few habitat requirements that must not be overlooked when setting up the environment for your hermit crab. In order to maintain their health, hermit crabs must live in a habitat that is set up to maintain the proper humidity levels.
In the wild, hermit crabs are accustomed to humidity of 70 to 80%. Even though they don’t live in the water, they do need a very moist environment. In fact, any lower than 70 percent and they will have difficulty breathing, because their gills need moist air. The average home, however, has an indoor humidity level much lower than 70 percent. Sustained exposure to this environment can have serious health consequences for your crab.
Luckily, there are a few simple methods you can use to increase the humidity of the cage. The key to increasing humidity is to keep as much moisture in the cage as possible. First off, use a glass aquarium, rather than an open-sided cage, because the solid sides will keep in moisture. Second, keep the water dishes full at all times. Your hermit crabs will require two dishes of water; salt water for bathing, and fresh water for drinking. Both will evaporate over time and therefore increase the humidity level in the tank. Additionally, adding a natural sea sponge to each dish can increase evaporation to create a more humid environment.
Whenever you add food to the tank or refill their water, make it a habit to mist the tank using a spray bottle. Doing so will increase the water content in the air. Remember to always use fresh, dechlorinated water with your hermit crab. Another way to increase the humidity is to moisten the sand or gravel at the bottom of the habitat so that the water can evaporate over time.
Maintaining the proper temperature can also affect the humidity level in the habitat. Hermit crabs thrive at temperatures between 70 and 80 degrees Fahrenheit. Use a heat lamp, if necessary, to bring the cage to the optimum temperature. Use a thermometer to ensure that the tank is neither too hot nor too cool. In a cold environment, you may notice decreased activity in your hermit crabs. An environment that is too hot can also cause damage to your crabs. Crabs that are overheated may develop a musty smell or brown liquid discharge, and may spend all their time hiding in any shade they can find. In addition, too-high temperatures often lead to lower humidity levels as all of the water evaporates out of the tank.
Once the cage is set up, attach a humidity gauge to the inside of the tank. This inexpensive device can help you determine the humidity levels so that you can add more water, if needed, to keep your crab comfortable. In order to thrive, hermit crabs need an environment that is both warm and humid to replicate the tropical climate they’re accustomed to living in.