Hermit Crab Poop

by | Aug 30, 2022

hermit crab poop

The questions about Hermit Crab Poop are commonly asked among the owners and on online forums around Hermit crabs. Many want answers to know if Hermit Crab excretes and how Hermit Crab poops. 

This blog post will discuss everything you need to know about Hermit Crab poop, from what it looks like, how often it poops, and how to clean your Hermit Crab tank or eliminate the excreta. 

Do Hermit Crab Poop?

Yes, Hermit Crab poop. Like all animals, the Hermit Crab finds a way to produce waste, but unlike most animals, it poops in its shells. 

And they don’t just poop; they also urinate. If you have Hermit Crabs, you should have noticed the waste they push out from inside their shells. 

Many people believe Hermit Crab doesn’t poop because they so do inside their shells. 

Because they live inside a borrowed shell meant for other species, the carapace doesn’t have a natural opening to release the waste. 

So, they poop in the shell and then empty it later. 

Also, the anus of the Hermit Crab is at the end of its abdomen.

What Does A Hermit Crab Poop Look Like?

Hermit crab feces

Now that you know that Hermit Crabs poop, let’s discuss what their poops look like. 

The Hermit Crab’s feces is either black or brown and usually sausage-shaped. 

They don’t smell like most poop, and many do not know if it is poop or not. 

If you see any black or brown thing lying outside their shell, it is their poop. 

How Often Do Hermit Crabs Excrete?

It is difficult to know how often a Hermit Crab defecates because, as I mentioned earlier, they poop in their shells, so it is difficult to know when they are doing so. 

But the idea that they only poop once in a while is all a myth. 

We only see the poop when the Hermit Crab decides to clear their shell and push the poop out. 

They do this using their legs to flick out the poop. That is when you see the poop just outside their shells. 

How Do Hermit Crabs Pee?

You must have heard that Hermit Crab pass out urine through their faces. While that sounds incredulous, it is true. That is because the urinary bladder of a Hermit Crab is beside its eyes. 

So, while they excrete in their shells, they urinate through their faces. 

When Hermit Crab wants to pee, they stick their heads out and pee. 

It may be difficult to see them urinate because they urinate only a small amount each time. 

Does Hermit Crab Eat Their Poop?

Yes, they are known to eat their poop. If you find your Hermit eating its poop, you should not worry, as it is normal. 

In their natural habitat, Hermit Crabs eat the poop of other species and their poop. 

How To Clean Hermit Crab Poop

Hermit Crab poops in their shells and flicks them out when they want to clean the carapace. 

Once it is outside the shell, it is your turn to do the cleaning. 

Besides eating the poop, Hermit Crab doesn’t like staying around their poop. So, it would help if you clean and tidy up their tank every week.

Spot clean: 

For thorough cleaning, you should take the Hermit Crab from the tank and put it in another container. 

I recommend you use a tall container to deter it from climbing and falling out. Once the Hermit Crab is out, remove all the other accessories in the tank and clean them with warm water. 

After that, place them somewhere to dry. 

Once you finish cleaning the accessories, you should use a spoon to remove the poop and other waste or debris in the tank. 

Once you’ve removed the wastes, use warm water and household vinegar to disinfect the entire tank. 

Clean the Shells: 

It would be best if you cleaned the vacant shells too. Some Hermit Crabs are known to leave one shell, move to another to poop, and then return to the previous shells.

I recommend having extra Shells available for your Hermit crabs. You can order some from a reliable seller. Check the link below. 

Buy shells for hermit crabs

Hermit Crab Shells

  • Natural, large and mixed colors
  • Quantity: 4 PC; Smooth Polished finish
  • Size: 1-3/4 Inch ~ 3 Inch
  • Opening Size: 1 ~ 1-1/4 Inch

(Amazon affiliate link)

So, to keep the tank clean and devoid of smell, you should clean all vacant shells. 

You should shake the shells to rid them of all poop or boil them if you want to clean them thoroughly. 

Boiling them for 5 minutes is enough to clean them. But make sure no Hermit Crab is in the shells if you decide to simmer them. 

Replace the Substrate: 

It would help if you replaced the substrate in your Hermit Crab tank once every three months or when you find out it is needed. 

I recommend a mixture of Eco Earth and play sand as a substrate. 

Eco Earth Substrate

  • Ideal substrate for Hermit Crabs
  • Eco-friendly
  • Naturally absorbs, breaks down odor, and waste product

(Amazon Affiliate link)

The cleaning may take a while, so you should plan accordingly. 

First, remove your Hermit Crab, place it in another container, and then empty the substrate outside. 

Once you’ve removed the substrate, you should clean the inside of the tank with a hose. 

You should remove and boil all vacant shells for 5 minutes and clean all accessories and decorations. 

Once you’ve done everything, put them back and replace the old substrate with a new one. 

Another way to ensure the cleanliness of your Hermit Crab and its tank is to provide two swimming spots. 

Add two bowls of water to your Hermit tank. 

Fill one with dechlorinated water and the other with salt water, respectively. 

Do not fill their baths or any of the bowls with tap water. I recommend dechlorinated bottled water. 

That will make your Hermit Crab drink and take baths to clean themselves and their shells. 

Regular baths and cleaning will help them stay healthy and live long lives.


Like other animals, Hermit Crab poops. 

They poop in their shells and later release it outside. 

Their poop has a brown and black color and comes in a sausage shape, so when you see anything of such near their shell, know it is their poop.

While Hermit Crab sometimes eats their poop, they usually don’t like staying around it. 

Ensure you clean your Hermit tank and change the substrate every two weeks.

About Me

Hi, I am Sarah! At Amado Pets we are passionate about pets and love sharing our knowledge and research with you. We strive to be the ultimate resource for you to learn all that you can about caring for your pet!