What foods are poisonous to hermit crabs?

Hermit crabs are fascinating and unique creatures that make wonderful pets due to their quirky personalities and low-maintenance care. However, it is important to keep in mind that hermit crabs are small animals with delicate dietary needs. They are omnivores, which means they require a balanced diet of both plant and animal sources. Providing your hermit crab with a well-rounded diet is vital to their health and wellbeing.

While a varied diet can ensure your hermit crab gets the necessary nutrients, it’s equally important to avoid any toxic plants, foods, or additives that could lead to illness or even death. In this blog post, we will discuss what foods are poisonous to hermit crabs and how to create a safe and healthy diet for them.

Basic Information on Hermit Crabs

Hermit crabs are decapod crustaceans with soft bodies protected by hard exoskeletons. They are found in various sizes and colors and can live for up to 20 years. They have an omnivorous diet and scavenge for their food in the wild.

In captivity, it is essential to provide a well-balanced diet that fulfills their nutritional needs. In addition to food, water and humidity are also critical factors in a hermit crab’s diet and health. Hermit crabs breathe through modified gills, which are sensitive to the salt and humidity in their environment.

Providing a Balanced Diet for Hermit Crabs

A balanced diet for a hermit crab includes sources of protein, carbohydrates, fiber, vitamins, and minerals. Here are some examples of each food group:

Protein Sources

Protein is essential for the growth and development of hermit crabs. Good sources of protein include insects, fish, and lean meats such as cooked chicken. However, make sure to remove any bones, as they can harm your pet.

Fruits and Vegetables

Hermit crabs enjoy a variety of fruits and vegetables, including apples, carrots, pears, and kiwis. These foods provide essential vitamins and minerals that your hermit crab needs to maintain good health. Some fruits and vegetables, such as bananas and papayas, are also a good source of fiber.

Calcium Sources

Calcium is essential for the growth and maintenance of hermit crabs’ exoskeletons. A good source of calcium is a cuttlebone, which is easily available at pet stores. Alternately, you can also sprinkle some ground-up eggshells onto your hermit crab’s food.


Water is essential for hermit crabs to maintain their hydration levels. Ensure that you provide your hermit crab with clean, fresh water. Since they need a humid environment to survive, make sure to mist the inside of their enclosure regularly to maintain a suitable level of humidity.

Avoiding Commercial Diets

Avoid feeding your hermit crab commercial diets or supplements that contain questionable ingredients. These products often contain preservatives, colorings, and sugar, which can harm your pet’s health.

Foods Harmful and Poisonous to Hermit Crabs

It is vital to keep in mind that not all foods are safe for your pet hermit crab. Some can be toxic and lead to severe health consequences. Here are some examples of foods that are poisonous or harmful to hermit crabs:

Foods High in Salt

Processed meats, salty snacks, and salted nuts are all high in salt and should be avoided. High salt levels can cause dehydration and lead to kidney failure in your hermit crab. High salt levels can cause stress in your hermit crab, which can lead to other health problems.

Foods High in Sugar

Just like humans, hermit crabs can experience issues from consuming too much sugar. Some of the sugary fruits that you should avoid feeding your hermit crab are grapes, which contain high levels of natural sugars. Artificial sweetened snacks or candies should also be avoided.

Chocolate and Cocoa Products

Chocolate contains theobromine, which can be toxic to hermit crabs. Theobromine can lead to seizures, muscle tremors, and respiratory problems. Be sure to keep any chocolate away from your hermit crab.

Pesticide-Contaminated Foods

There is a high risk of pesticide contamination in non-organic fruits and vegetables. If you must feed your hermit crab fruits or vegetables, you should wash them thoroughly before feeding them to your pet.

Insecticides and Herbicides

Insecticides and herbicides can be harmful to your hermit crab if they consume contaminated insects or plants. Always be sure that the species of the plant is not poisonous before you give it to your hermit crab. Make sure to avoid feeding your hermit crab insects that you’ve caught in the wild.

Spices or Seasonings

Spices such as onions and garlic are toxic to hermit crabs. Foods containing artificial flavors, colors, or preservatives should also be avoided.

Citrus Fruits

While some fruits can be provided for potassium and vitamins, citrus fruits such as oranges, lemons, and limes, should be avoided as they can cause gastrointestinal problems, which hermit crabs are highly susceptible of.

Some Nuts

Some nuts, like almonds and peanuts, can contain molds, which can produce toxic substances that harm hermit crabs. Nuts are also high in fat, which can lead to obesity and other related health problems.

Preventing Accidental Poisoning

You can prevent accidental poisoning by ensuring that your hermit crab gets a balanced and varied diet. Stick to the safe foods as mentioned above and avoid any questionable products that may contain harmful ingredients.

It’s important to store the food correctly by keeping it in containers with a tight-fitting lid and storing them away from potential contaminants such as cleaning products or chemicals.

Make sure to keep your hermit crab’s environment clean by avoiding overfeeding and remove any uneaten food promptly. Uneaten food can become moldy and toxic, which can cause your hermit crab to become ill.

Signs of Poisoning and What to Do

If your hermit crab shows signs of poisoning, such as lethargy, loss of appetite, or discolored limbs, take immediate action. Remove any potentially toxic food immediately and replace it with something safe. Monitor your hermit crab closely and look for signs of improvement.

If your pet’s condition doesn’t improve, don’t hesitate to contact a veterinarian that specializes in hermit crabs. They can provide you with further advice and ensure that your pet receives any necessary treatment.


Hermit crabs are low-maintenance and fascinating pets. Ensuring they receive a balanced and varied diet is vital to their health and wellbeing, and it’s equally important to avoid the toxic plants, foods, or additives that can lead to illness or even death. Understanding what foods are poisonous to hermit crabs will allow you to keep your pet safe and healthy for years to come. Remember to follow the guidelines and prevent accidental poisoning by maintaining a clean environment, storing food correctly, and monitoring the diet.