How Long Can Hermit Crabs Go Without Water


by Simon Griffiths


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If you’ve typed this into your search engine, you’re probably a hermit crab owner who wants to go away for the weekend or a significant period of time, or taking care of a friend’s hermit or maybe just a curious reader.

Whichever the case, this article is here to answer your question.

Hermit crabs are a great choice of pet, but even if they are independent creatures, they still need a great deal of care. Consequently, knowing all these details is fundamental to a hermit crab owner the minute they step into a pet store.

Ready to learn?

Let’s dive in!


Hermit crabs, the basics

There are two types of hermit crabs;

  1. i) Land hermit crabs
  2. ii) Marine hermit crabs

Marine hermit crabs spend most if not all of their lifetime in seawater, and they do so for their survival. Land hermit crabs can survive on land, but they need close proximity to water.

They do not necessarily just stick to the beach, but they can have their habitats in marshy areas and forests with water nearby.

Hermit crabs are omnivorous scavengers, eating everything from dead aquatic animals to aquatic plants, vegetables, and fruits.

Hermit crabs and crabs are not entirely similar, even though they are both referred to as crabs.

Differences between a true crab and a hermit crab.

One of the key differences includes the fact that hermit crabs walk forward while normal crabs walk sideways. Another difference is that true crabs have two claws of equal size while hermit crabs have two claws, with one being bigger than the other. Hermit crabs have a hard exoskeleton for the front half of their bodies and a soft exoskeleton for the rest while a true crab only has a hard exoskeleton.

How do hermit crabs breathe?

Hermit crabs breathe oxygen through their gills. This applies to both land hermits and marine hermits. They absorb oxygen from water via their gills, so they do not take in oxygen directly from the air. The oxygen is then absorbed into the blood vessels of the hermit. Their gills are highly vascularized which makes it easier for the oxygen to be absorbed.

For land hermits, their modified gills enable them to be able to absorb oxygen from water without necessarily being submerged in water. They need to keep their modified gills moist so that they can consistently have an oxygen supply. Their borrowed shells help them store water so that they can always hydrate their gills.

The type of water also has specified roles; freshwater mainly keeps the gills moist while salty water helps in regulating the respiratory system of the hermit crab.

Related Can A Hermit Crab Breath Underwater? Does it Breathe Water or Air and How Does it Breath?

How long can hermit crabs go without water?

This is the part of the article meant to answer your question.

First of all, having established that there are two types of hermit crabs, their needs are definitely different.

Aquatic or marine hermit crabs live in water entirely, so staying out of the water is dangerous for them. Their body mechanism will not allow them to breathe outside water so they cannot survive for more than a few minutes. For land hermit crabs, they need to consistently replenish their supply of water otherwise they cannot moisten their gills for breathing. When their water supply is depleted, they can still survive but only for two weeks maximum. If the environmental conditions are very harsh and it is too hot, this period is shorter.


Can hermit crabs drown?

Even though hermit crabs are aquatic animals, they can still drown.

Marine hermit crabs will not drown because it is their home. On the other hand, land hermit crabs can only be submerged in water for around 15 minutes to an hour depending on their size.

Related Do Hermit Crabs Live in Water? And Can They Drown?

Can hermit crabs eat pet food?

If you have a pet hermit, you might be tempted to give them some dog or cat food to save on costs or just to experiment. However, this is not recommended because dog food and cat food have specific elements and chemicals which are specific to those animals and so it may be harmful to hermit crabs. Some foods can be eaten by both, including canned meats.

Related  List of Foods That Hermit Crabs Can Eat

Is tap water good for hermit crabs?

Tap water can sometimes have too much chlorine, chemicals, and metals. These toxins are harmful to hermit crabs. If you must use tap water, use a de-chlorinator. Read the instructions on the bottle properly so that you do the right thing and keep your hermit safe. If you do not want to dechlorinate your water using the conditioner, you can boil it or leave it out for some time so that the harmful elements can evaporate.

If you can, use bottled water instead of tap water.

Related How To Make Safe Saltwater for Hermit Crabs

Why isn’t my hermit crab eating?

Hermit crabs do not really eat much to begin with, so sometimes a bit of a break from food should not be a cause for concern. They can actually go for several days without eating food or water.

Sometimes hermit crabs stop eating because of excessive stress, being bored from eating the same bland boring foods, illness and retreating into the sand for molting purposes.

Please note that you do not need to feed your hermit crab multiple times a day, feeding them fresh food once a day is enough.  Before giving them their next meal, make sure you take out the food that was there previously.


To sum up, a hermit crab’s ability to survive without water depends on the type of hermit crab and its environment.

Marine hermit crabs will absolutely not survive for long outside the water, since they cannot breathe. Land hermit crabs draw water from their environments and store water in their shell so they do not need to be at the water constantly. However, if this supply runs out, they can only stay alive for two weeks.

If you need to travel, make sure there is enough supply of water in the tank so that the hermit can survive. If the water you’ve left is in a bowl or a small container, make sure the hermit is able to climb in and out of it easily. Make sure it does not endanger the hermit crab, because they can drown.

Simon Griffiths

Hi guys, my name is Simon, a fellow pet lover. I love everything about traditional and exotic pets so I am here to help you create a better home for your pets.

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