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Hermit Crab Care Guide

Tips for home, health and fun


6 things to know about your Hermit Crab

  • Hermit crabs can live up to 10 years
  • They can grow up to 6 inches long
  • They live on land, not in water, but do require water & moisture in order to replenish shell water
  • Hermit crabs can be handled, but will pinch if threatened or scared
  • They molt (shed their skin) and change shells as they grow
  • The shell is important because they do not have a hard external shell for protection. 3-5 shells per crab should always be available

How do I set up my hermit crab's home?

  • Hermit crabs thrive in a tropical environment. Despite their name, hermit crabs are social creatures and can live together in pairs or groups.
  • Choose a terrarium with at least 5 gallons of space for every 2 crabs. The terrarium should have a hood to keep humidity in and keep your hermit crab from escaping. Keep the terrarium in a low-traffic area out of direct sunlight and away from drafts.
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What to put in the (hermit) crab shack

  • Line the bottom of the terrarium with 2 to 3 inches of silica play sand, soil and/or coconut fiber; your hermit crabs will burrow into it when they're molting.
  • Create several hiding places in the terrarium.
  • Furnish the habitat with at least 3-5 larger empty seashells per crab, to use as future housing. As they grow into these shells, add slightly bigger ones.
  • Add a shallow dish with fresh water and marine-grade saltwater for your crab to soak in. Make sure it is dechlorinated water, chlorine is harmful to crabs. Make sure the sides of the dish are low enough that the crab can get out easily. If your terrarium includes hermit crabs of different sizes, put a rock in the bowl so the smaller ones can climb out.
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Heat & light

  • The terrarium temperature should be 75-85 degrees Fahrenheit (23-29 Celsius) during the day and 65-75 degrees F (18-24 C) at night. Use a thermometer to monitor the temperature.
  • If you use an under-tank heater, cover it with at least an inch of bedding, so your crabs don't get uncomfortably hot.
  • Hermit crabs thrive at humidity levels between 70% and 80%. Mist their terrarium with non-chlorinated water as necessary and use a hygrometer to keep track.
  • Put a fluorescent or LED bulb in the terrarium hood to light the habitat for 8 to 12 hours a day. Do not use high-output UVB lighting for hermit crabs.
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What do I feed my hermit crab?

Hermit crabs eat pellet food, supplemented with vegetables and fruit.

  • Hermit crabs take small bites and eat very slowly, usually at night.
  • Small crabs sometimes don't have claws big enough to grab onto pellet-type food. Feed small crabs 1 teaspoon of powdered hermit crab food, or pellets crushed into powder.
  • Supplement your hermit crab's diet with chopped dark, leafy vegetables such as kale or broccoli and chopped fruit such as apple, grapes and banana. Put the fruit or vegetables in your crab's terrarium in the evening, and remove any leftovers in the morning.
  • Hermit crabs are extremely sensitive to metal. Be sure their food and water bowls are ceramic or another nonmetal, non-porous material.
  • Your hermit crab should have access to fresh, clean water and marine-grade salt water at all times. Always add a dechlorinator or water conditioner to tap water before putting it in your crab's water dish
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How do I keep my hermit crab healthy?

Hermit crabs can be vulnerable while molting, because their bodies are soft. Isolate them from their roommates during this time.

Don't drop hermit crabs onto a hard surface; doing so can injure or kill them.

Never release hermit crabs into the wild. They aren't likely to survive and if they do, they can harm the local ecosystem.

If you notice any of these symptoms of illness or distress, talk to a veterinarian:

  • Decreased appetite or activity
  • Staying outside of the shell
  • Excessive molting
  • Lost claws or limbs
  • Strong odor from inside the shell


  • Use caution when handling pets and remember they may bite or scratch (especially when stressed).
  • ALL ANIMALS can potentially carry viral, bacterial, fungal, and parasitic diseases contagious to humans.
  • Thoroughly wash your hands with warm, soapy water before and after contact with any pet or its habitat.
  • Adults should assist children with hand washing after contact with a pet, its habitat or aquarium water.
  • Do not use soaps or detergents to clean aquarium or décor, since they are toxic to hermit crabs.


Pets purchased at PetSmart are part of our exclusive Vet Assured™ program, designed by PetSmart veterinarians to help improve the health and well being of our pets.

Our vendors meet a high standard in caring for pets and screening them for common illnesses. This program also includes specific standards for in-store pet care.


If your pet becomes ill during the initial 14-day period, or if you're not satisfied for any reason, PetSmart will gladly replace the pet or refund the purchase price.


Freuently Asked Questions (FAQs)


What do hermit crabs eat?

What your hermit crab eats will vary depending on their size. Crabs sometimes don’t have class big enough for pellet food, so they need powdered hermit crab food. Hermit crabs also eat leafy vegetables and chopped fruit.


Are hermit crabs good pets?

Hermit crabs can make great pets for anyone who likes them! They are relatively low maintenance and beautiful to look at as they explore their habitat.


How long do hermit crabs live?

Hermit crabs can live up to 10 years old and can grow up to 6 inches long.