The Ultimate Guide to Hermit Crab Care: Creating a Thriving Habitat

Hermit crabs are fascinating and relatively low-maintenance pets, making them a popular choice for both children and adults. However, while they may seem simple to care for, providing them with the right environment and meeting their specific needs is crucial for their health and well-being. This comprehensive guide will walk you through every step of hermit crab care, ensuring your shelled friends live long, happy, and fulfilling lives.

Understanding Hermit Crab Needs

Before you bring any hermit crabs home, it’s essential to understand their natural habitat and behaviours. Hermit crabs are not truly crabs; they are decapod crustaceans that lack a hard exoskeleton of their own. Instead, they rely on abandoned snail shells for protection, and they are constantly seeking out larger shells as they grow. These fascinating creatures are also social and thrive in groups, so avoid keeping them solitary.

There are two main types of hermit crabs commonly kept as pets: the Caribbean Hermit Crab (Coenobita clypeatus) and the Purple Pincher Hermit Crab (Coenobita compressus). Both have similar care requirements, but it’s good to know which species you have.

Key needs of hermit crabs include:

• Proper Habitat: A spacious, well-ventilated enclosure with specific substrate and humidity levels.
• Suitable Shells: A variety of shells of appropriate size for each crab.
• Appropriate Diet: A balanced diet that meets their nutritional requirements.
• Fresh Water and Salt Water: Access to both types of water for drinking and bathing.
• Correct Temperature and Humidity: These are critical for molting and overall health.
• Social Interaction: They are social animals and should be kept in groups if possible.

Setting Up Your Hermit Crab Habitat

The habitat is the cornerstone of hermit crab care. Here’s a step-by-step guide on setting up a comfortable and enriching environment:

1. Choosing the Right Enclosure

• Size Matters: A 10-gallon aquarium can house 2-3 small hermit crabs, but larger is always better. A 20-gallon long aquarium or larger is ideal for a small group, and you should increase the size as your crabs grow or you add more members to your colony. Consider that they will get larger over time and a larger tank means less frequent maintenance.
• Material: Glass aquariums are excellent choices as they are easy to clean, allow for good visibility and retain humidity well. Avoid using wire cages, as they don’t retain moisture and can be difficult for crabs to climb on.
• Ventilation: A secure lid is crucial to prevent escapes and maintain humidity, but it must also have some ventilation. Mesh screens are a good choice to allow air flow while containing your crabs. Avoid lids that seal entirely shut.

2. Selecting the Right Substrate

The substrate in your hermit crab tank is important for burrowing, humidity retention, and shedding. A proper substrate is essential for successful molting. Here are the best choices:

• Play Sand: Uncolored, play sand is a staple, and should be available in a deep layer. Ensure you source a sand that is not treated with any chemicals or additives.
• Coconut Fiber (Eco Earth): Coconut fiber provides a fluffy, moisture-retaining base that is ideal for burrowing.
• Substrate Mix: Mixing play sand and coconut fiber in a ratio of 5:1 is highly recommended. This mix provides the right consistency and moisture-holding properties for hermit crabs to easily burrow and molt.
• Substrate Depth: The substrate should be at least 6 inches deep, but deeper is better, especially for larger crabs. Allow for at least 3 inches per crab. They need to be able to fully bury themselves to molt safely.
• Substrate Maintenance: Spot clean the substrate daily to remove uneaten food or waste. Change the entire substrate every few months, or more frequently as needed, or when a deep clean is needed.

3. Providing Adequate Humidity

Hermit crabs need high humidity to breathe, keep their gills moist and molt properly. Aim for a humidity level between 70-80%. Here’s how to achieve that:

• Hygrometer: Use a hygrometer to monitor the humidity levels inside the tank.
• Misting: Mist the tank with dechlorinated water one or two times per day, or more as needed, to maintain proper humidity.
• Deep Substrate: A deep, moist substrate (such as the sand and coconut fiber mix) will naturally help maintain humidity.
• Water Bowls: Having larger water bowls (one fresh and one salt) in the tank will add to the humidity levels. Make sure the bowls have a way for the crabs to exit.

4. Maintaining the Correct Temperature

Hermit crabs thrive in warm environments. The ideal temperature range is between 70-80°F (21-27°C). Avoid placing the tank near drafts or in direct sunlight. How to manage temperature:

• Thermometer: Place a thermometer inside the tank to monitor the temperature accurately.
• Under-Tank Heater: Use an under-tank heater placed on the side or back of the tank (never under the bottom). This will provide a gentle, consistent heat source.
• Heat Lamp: An overhead ceramic heat emitter can also be used to provide supplementary warmth, especially for larger tanks, but should be used in conjunction with an under-tank heater. Be cautious with heat lamps as they can dry out the tank quickly and make sure the light does not disturb the crabs sleeping patterns.
• Avoid Hot Rocks: Never use hot rocks, as they can cause burns to your hermit crabs.

5. Providing a Variety of Shells

Shells are the most important accessory for your hermit crabs. They use shells for protection, comfort, and to molt. A variety of shells are essential:

• Shell Selection: Offer a variety of shells, larger than the current shells, made from a variety of materials. Turbo shells (Turban Shells) are a good option, as they provide the right weight and shape for a wide range of hermit crabs. Make sure the openings are rounded, not oval. Other shells such as shells from land snails can also be good options.
• Number of Shells: Ensure there are at least 3-5 extra shells per crab and replace the selection regularly.
• Cleanliness: Clean shells thoroughly by boiling or baking them before adding them to the tank. Avoid using shells that have been painted or treated with chemicals.
• No Damage: Inspect shells for cracks or damage. Damaged shells are unsafe for your crabs.

6. Setting Up Water Dishes

Hermit crabs need access to two types of water: fresh water and saltwater. These are vital for hydration, maintaining gill moisture and regulating the salt levels in their body.

• Fresh Water Bowl: Provide a shallow dish of dechlorinated fresh water (tap water treated with a dechlorinator). The bowl should be shallow enough for your crabs to easily enter and exit without drowning. Consider adding some pebbles or a sponge to help them climb out.
• Saltwater Bowl: Provide a second shallow bowl of saltwater, using marine salt mix designed for aquariums (not table salt). Follow the instructions on the salt mix container for the correct salinity. Change the salt water regularly, at least every few days, and monitor the salinity to ensure it is at the correct level.
• Bowl Size: Choose bowls that are large enough for your crabs to submerge themselves if they choose, but shallow enough to avoid any accidents.
• Cleaning: Wash and disinfect water bowls regularly to avoid bacteria buildup.

7. Adding Climbing and Enrichment Items

Hermit crabs are curious and active creatures. Adding enrichment items will promote exercise and exploration:

• Branches and Cork Bark: Add pieces of driftwood, cork bark, and cholla wood for climbing and hiding.
• Plants: You can add safe, non-toxic live or fake plants such as spider plants, peperomias, or pothos. Real plants will help improve the overall humidity of the tank.
• Rocks and Caves: Include rocks, caves, or small ceramic pots to offer hiding places and opportunities for exploration. Make sure the items are large enough so they are stable and cannot be easily tipped over by the crabs.
• Hemp rope: Hemp rope provides a good climbing surface for hermit crabs and adds additional enrichment to their habitat. Ensure the rope is natural and untreated.

Feeding Your Hermit Crabs

Hermit crabs are scavengers in nature, and they have a varied diet. It’s important to offer a balanced mix of fresh and dried foods. A varied diet is crucial for their health, and ensures they are receiving a proper balance of vitamins and minerals. Here are some ideas:

1. What to Feed

• Commercial Hermit Crab Food: Use this as a base for their meals. It is important to read the labels and ensure the ingredients are high quality. Avoid foods that are heavy in artificial colours and preservatives.
• Fresh Fruits and Vegetables: Offer small portions of hermit crab safe fruits and vegetables. Good options include: apples, bananas, berries, carrots, spinach, broccoli, and leafy greens. Be sure to rinse any fresh produce well before placing it in the tank.
• Protein: Hermit crabs need protein to stay healthy. Sources of protein include: freeze-dried shrimp, mealworms, cooked unseasoned eggs, small pieces of cooked meat and fish, and unsalted nuts and seeds.
• Calcium Sources: Calcium is important for shell growth and health. Offer cuttlebone or powdered calcium supplementation that can be mixed into their food, or placed directly in the tank.
• Other Options: They can also enjoy small amounts of unsweetened coconut flakes, oats, popcorn (unsalted and unbuttered), and dried seaweed.

2. How to Feed

• Food Dish: Place food in a shallow dish or bowl that is easily accessible to the crabs.
• Amount: Offer small portions daily and remove any uneaten food after 24 hours to prevent mold growth.
• Variety: Rotate the types of food you offer to ensure a balanced diet.
• Water: Never feed or give anything other than pure water and safe foods to your crabs.
• Avoidance: Never give your hermit crabs citrus fruits, onions, garlic, or processed foods that have been seasoned.

Molting: A Crucial Process

Molting is a vital part of a hermit crab’s life cycle. They shed their old exoskeleton to grow larger, and this process can take days or even weeks. It is critical to provide the proper environment to support them through this vulnerable stage:

1. Recognizing Molting Signs

• Lethargy: Crabs become less active and may spend more time buried.
• Dull Coloration: Their exoskeleton may appear dull or faded.
• Loss of Appetite: They may lose interest in food.
• Burrowing: They will dig deep into the substrate to molt.

2. Providing a Safe Environment

• No Disturbances: Never dig up or disturb a crab that is buried, or that you suspect is molting. The molting process is fragile and any disturbance could result in the death of the crab.
• Deep Substrate: Ensure the substrate is deep enough for the crab to bury itself completely.
• Humidity and Temperature: Maintain stable humidity and temperature levels.
• Patience: The molting process can take weeks, or even months for larger hermit crabs. Be patient and avoid handling the crab until it has fully hardened its new exoskeleton.
• Leave the Exoskeleton: Never remove the old exoskeleton from the tank. The crab will eat it for nutrients as part of the molting process.

Maintaining Your Hermit Crab Habitat

Regular maintenance is crucial for the health of your hermit crabs. Here’s a checklist to follow:

• Daily:
  • Remove any uneaten food.
  • Check water levels and humidity. Mist as needed.
  • Spot clean the substrate by removing any visible waste.
• Weekly:
  • Change the water in both the fresh and saltwater dishes.
  • Inspect shells and offer new options as needed.
  • Check temperatures with a thermometer.
• Monthly:
  • Deep clean the substrate or replace it if needed.
  • Wash and disinfect decorations and climbing items.
  • Assess your crabs general health and behaviour. Check for any signs of sickness.

Recognizing and Addressing Health Issues

Hermit crabs are generally hardy, but they can be prone to certain health issues. Regular observation will help you spot potential problems early:

• Lethargy: A crab that is inactive or lethargic may be experiencing stress or sickness.
• Limp Limbs: Limp limbs can indicate a problem with molting or that the crab has experienced an injury.
• Missing Limbs: If you notice your crabs are missing limbs, this could be a sign of aggression from other crabs. Separate any crab that is missing limbs. Limbs can be regrown during molting.
• Antennae Issues: If the antennae are limp or drooping this could indicate a health issue.
• Mites: If you notice tiny, red mites crawling on the crab, that is a sign that you need to deep clean the tank. Remove the crab and place in a temporary container while you clean the main habitat.
• Respiratory Issues: Gasping or labored breathing, can indicate a problem with humidity levels. Adjust as necessary.
• Shell Issues: Shells should be cleaned often, and shells that are cracked or damaged should be removed.

If you observe any of these signs, take action promptly. If symptoms worsen, consult a veterinarian familiar with exotic pets.

Handling Hermit Crabs

Hermit crabs should be handled with care and gentleness. Avoid picking them up by their shell or limbs. Instead, scoop them up gently with your hand. Always make sure your hands are clean and free from any soaps or lotions. If you need to handle your crabs, keep it to a minimum as they can easily become stressed and it can trigger aggression towards other crabs. Hermit crabs do not need to be handled or played with, as they do not bond with their owners.

Conclusion

Caring for hermit crabs is a rewarding experience that brings the wonders of nature into your home. By providing a suitable habitat, a balanced diet, proper temperature, and humidity, and carefully observing your crabs, you can help them thrive and live long, happy lives. This guide provides you with the necessary information to become a successful and responsible hermit crab owner. Enjoy watching these fascinating creatures and the unique joy they bring!