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Choosing the Right Hermit Crab Tank Size

Choosing the Right Hermit Crab Tank Size
The purpose of this blog is to share general information and is written to the author's best knowledge. It is not intended to be used in place of veterinary advice. For health concerns, please seek proper veterinary care. In addition, as an Amazon Associate I earn from qualifying purchases.

Hermit crabs are great starter pets to have. They require little care and are suitable for people of nearly any age.

They are relatively self-sufficient creatures that do not need any personal maintenance. Hermit crabs know what to do naturally, and they will eat and drink as they please.

You will see your hermit crabs freely roaming around in their tanks when they are happy with their environment. Knowing what size to select is a big factor in how active they will be and how they function as a whole.

Unlike humans, hermit crabs do not require ample decor or aesthetic accessories. They are simple creatures with very specific needs to survive.

As you learn more about them and keep these facts in mind, you will soon find out exactly what your role will be. You will provide them with the necessary space, and they will take care of the rest.

Because they are so easy to care for, a common misconception is that they do not need much in their tank. For this reason, people are quick to buy the cheapest and smallest tanks to house their hermit crabs.

Even though they are relatively low-maintenance creatures, they still do need space to move around, take a dip, and have plenty of water for drinking.

They are both land-dwelling and water-dwelling, though you will primarily see your hermit crab on land. There are moments when a hermit crab will want to be inside water and may even submerge its body in water for hydration.

The cheapest, smallest option is not always going to be the best for a pet that does need to have space to be outside of water and inside of it. Knowing what you need to house a happy and healthy hermit crab (or multiple) is very important for this reason.

The Bare Minimum

Wanting to take the easiest approach is natural. You elected to keep a hermit crab or hermit crabs because of their low-maintenance nature.

There is nothing wrong with this, but you still need to be aware of what the standard is when it comes to the bare minimum. There is such a thing as a tank that is too small, and you never want to crowd even one single hermit crab in its tank.

If you only plan on having one hermit crab, you do not want to go for a tank any smaller than 10 gallons. The 10-gallon size is seen as the standard for one to three hermit crabs.

This size will give your hermit crab plenty of room to thrive and live healthily. Even though a hermit crab does not grow to be very large, it still needs room to walk around freely.

Hermit crabs are active creatures. They enjoy moving around their habitat and a wide variety of options for walking, soaking, and resting.

Having a tank that is durable is also recommended. Instead of opting for a plastic container that is generally used for transferring pets, you should go for something made of glass and is clear on all sides.

Plastic containers are usually what hermit crabs will come in when you get them, but this is not a sufficient habitat that should be used permanently. Many people make the mistake of continuing to use the carrier as a tank, but they are not equivalent.

Your hermit crab will require two separate dishes of water, one containing freshwater and the other containing saltwater. Being able to comfortably place these dishes of water along with having plenty of dry land for your hermit crab in between is essential.

Keeping your hermit crab in a plastic container also brings forth the risk of keeping it in a dirty environment. Plastic will likely grow dirty over time, and it will not make for a healthy environment for your hermit crab.

Glass is more sterile, and anything that grows on the glass is typically going to be safe for your hermit crab. It is also a lot less likely to be knocked over or bumped into.

Multiple Hermit Crabs

As mentioned, a 10-gallon tank is appropriate for up to three hermit crabs. Many people like to get more than one so they can keep each other company, and this is a viable option.

If you want to get more than three hermit crabs, it is strongly suggested that you size up to a 20-gallon tank. This might seem like an excess of space, but you need to make sure they can all move around and soak without being crowded in the tank.

Having two water dishes for multiple hermit crabs also means they will need to be bigger, so it makes sense that you would need a larger enclosure. In a 20-gallon tank, you can put around six regular-sized hermit crabs inside.

You can make exceptions if the crabs are not as large or as small as the typical size. If they are tiny, you can fit up to 10 comfortably.

Be aware that large hermit crabs will only be happy in a 20-gallon tank if there are around four of them total. If you need more clarification, you can ask the pet store what size they are.

Below is a helpful chart that will inform you how many hermit crabs you can fit into various tanks:

  • 5-gallon: This is not a recommended tank size for even just one hermit crab. There will not be enough space inside the tank.
  • 10-gallon: This is a tank suitable for one to three hermit crabs. It can comfortably house all of them while still including everything they need.
  • 20-gallon: This tank is great for up to six hermit crabs. It is also only recommended to get six or fewer if you are getting hermit crabs for the first time.
  • 30-gallon: This size can comfortably house around 10 to 12 hermit crabs. It is only recommended if you have prior experience with caring for multiple hermit crabs.
  • 40-gallon: This is an ideal size if you have experience and are planning on keeping around 13 hermit crabs inside.
  • 50-gallon: This is a tank that only very experienced people opt for when it comes to hermit crabs. Up to 16 hermit crabs can live comfortably here.

Now that you have a better idea of what kind of tank you need, you should be able to plan for how many hermit crabs you would like to raise. Try not to take on too many at once because you can always get a few more once you become comfortable with the process.

A common mistake is to buy a bunch of hermit crabs because they are relatively inexpensive pets and require little maintenance, but space is very important. It is a general rule that the more space you have, the happier your hermit crabs will be.

There is always the option to upgrade your tank setup if you do decide you would like to get more hermit crabs in the future. Go with the most sustainable and budget-friendly option to begin.

If you decide to expand, you can slowly begin to upgrade your setup before you introduce any new hermit crabs to the enclosure. It is better to make this change gradually instead of taking on more than you can care for from the beginning.

With this in mind, you should be able to learn how hermit crabs function before going all out with a very large tank. Hermit crabs are easy to care for, but this does not make them any less of a commitment than any other pet.

Final Thoughts

Hermit crabs are fun pets to keep and interesting creatures to observe. Even though they are not as hands-on as a cat, dog, or bird, your hermit crab(s) will definitely keep you busy with changing out their water and feeding them regularly.

A happy and healthy hermit crab is one that is active. While a hermit crab might be still for some time outside of water, it should still have the desire to take multiple soaks a day.

Because hermit crabs can hydrate by drinking water as they scoop it from their claws to their mouths and also through soaking water under their shells, the level of submersion they get is essential.

Each hermit crab in the tank needs enough space for each crab inside to freely drink water and soak in water. This is why it is important to never overcrowd a tank or use a container that is only made for transportation.

If you stick to these basic rules, you will be able to successfully raise your hermit crabs in the best habitat possible. Keep an eye on them, and their behavior will give you a hint as to what they need.

Active hermit crabs are healthy hermit crabs, and you will see them going from land to water if they are happy and have ample room. They do not need much, but your effort to select the best size tank will prove to be very important.