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What Is the Optimal Hermit Crab Tank Size?

What Is the Optimal Hermit Crab Tank Size?

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This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addition, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

Buying hermit crabs as pets can be a great experience. If you don’t have a lot of room for larger pets in your home, you’ll likely be satisfied with these interesting creatures.

Before you commit to buying hermit crabs as pets, it’s wise to learn about them. You want to make sure that you can meet the basic care needs of these crabs.

For instance, it’s important to make sure that you have a tank that’s the right size. What size tank do you need for hermit crabs anyway?

Keep reading to learn about hermit crab tanks. You’ll learn about tank size recommendations as well as other important information that you need to consider before moving forward.

How Many Hermit Crabs Per Gallon?

It isn’t necessarily easy to say how many hermit crabs should be in a tank without more information. You see, hermit crabs aren’t all the same size.

Depending on the size of the crabs, you might need more or less space. Many people say that one gallon of space per hermit crab is acceptable.

However, this isn’t going to be true if the crabs are larger. Hermit crabs grow as they continue to molt and age.

You want the hermit crabs to have enough room that they won’t feel cramped. It’d be best to have a terrarium that’s large enough for all of the crabs to live comfortably.

Knowing this, you shouldn’t stick to a strict number when figuring out how many hermit crabs can fit in the tank. It’s better to think about the size of the crabs and to avoid overcrowding the terrarium.

How Many Hermit Crabs in a 5-Gallon Tank?

How many hermit crabs will fit in a 5-gallon tank will depend on the size of the hermit crab. You can potentially fit up to five hermit crabs in a tank of this size.

If the crabs are larger, you’d be better off only keeping a few crabs in a 5-gallon tank. Hermit crabs that are around one inch will be fine when they have at least one gallon of space.

Do your best to keep this in mind and make good decisions. You don’t want the hermit crabs to feel like they have to compete with each other too much.

This could lead to various issues. You’re truly better off not crowding a hermit crab habitat.

How Many Hermit Crabs in a 10-Gallon Tank?

Technically, you might be able to fit up to ten hermit crabs in a 10-gallon tank. As mentioned above, crabs that are one inch will be fine with one gallon of space.

Larger crabs will require more space. Thus, you’ll need to make a decision based on the size of the crabs that you wish to care for.

In some cases, it might be best to keep three or four crabs in a 10-gallon tank. Don’t cram too many crabs in a tank if you don’t know if they can live comfortably.

It’s better to consider the types of crabs that you have and their size. Do whatever is best for your hermit crabs.

How Many Hermit Crabs in a 20-Gallon Tank?

If the hermit crabs are only one inch, you could fit up to twenty of them in a 20-gallon tank. Of course, hermit crabs might be much larger than this.

Larger crabs would need more space and you wouldn’t want to try to force twenty of them into a tank like this. A 20-gallon tank could be perfect for seven to ten hermit crabs depending on the size of the crabs.

Do a little research based on the size of the hermit crabs that you own. You don’t want to get an overly large tank either for reasons that will be discussed later.

A little tank is just not going to be the best situation. A 20-gallon tank can be great, but it is possible to put too many hermit crabs inside.

What’s the Best Tank Size?

Generally, it’s best to buy a 10-gallon or 20-gallon tank for hermit crabs. Keep in mind that hermit crabs grow as they get older.

Even if your crabs are small now, they’re going to get larger as the years go by. They will require more space as they get older.

If you buy a larger tank for the hermit crabs to live in, it’ll be easier to get good results. You won’t have to worry about buying a new habitat for the crabs a year or two down the line.

Many enthusiasts say that a 10-gallon or 20-gallon tank will be good for three hermit crabs. That might seem like a small number of crabs, but remember that you don’t want to overcrowd the tank.

The crabs will grow and they shouldn’t have to live in a cramped environment. If you want to keep larger groups of crabs, you’ll likely want a bigger tank such as a 50-gallon tank.

One reason you’ll want a big tank for the crabs is so you can give them a stimulating environment. You want to be able to place interesting toys in the tank.

Hermit crabs are very playful creatures that like to climb and interact with the environment. The tank should have room for driftwood, random toys, and structures that the hermit crabs can climb.

Going with a smaller tank would limit your ability to make the environment stimulating for the crabs. Also, you want the crabs to have hiding spots around the tank for when they want to get away from each other.

Don’t Go with a Tank That’s Way Too Big

Going with a tank that’s way too big will be much tougher to maintain. This is because you need to monitor the temperature of the tank and the humidity level.

You’ll need a heater to keep the tank warm enough for the hermit crabs. A larger tank will require a more powerful heater and that might be more expensive.

The same thing can be said for the humidifier. A larger environment will require a better humidifier to keep the humidity level where it needs to be.

Both the temperature and the humidity need to be right for the hermit crabs to remain healthy. This isn’t hard to accomplish, but you can make mistakes that will cause your hermit crabs to experience problems.

Ensure that you keep the hermit crab tank between 75 degrees Fahrenheit and 85 degrees Fahrenheit. You also need to keep the tank away from sunny windows or it could have an impact on the temperature.

The humidity level in the tank must be kept between 75% and 85%. Hermit crabs need high humidity to be able to breathe properly.

These creatures possess modified gills that allow them to breathe oxygen. If they don’t have enough moisture in the air, they won’t be able to breathe at all.

So long as you’re using a humidifier in the tank it’ll be easy to keep the humidity in the right range. Some people also use methods such as misting the tank and keeping wet sponges in the tank to raise the humidity level.

All of these methods will be harder if the tank is bigger than it needs to be. Go with a tank that is more than big enough without being impractically large.

Can Hermit Crabs Live Alone?

Some people choose to keep hermit crabs by themselves. You might be able to raise a single hermit crab if you take care of it well and give it attention.

However, these are social creatures that do better when kept in small groups. You might not know this, but hermit crabs can get quite lonely when they’re forced to live in solitude.

A hermit crab may even die of loneliness under certain conditions. Therefore, it makes sense to keep hermit crabs in groups of three or four.

Your hermit crab will like being able to interact with friends. Hermit crabs will be much happier when they have others of their own kind to play with.

You can also interact with hermit crabs to get them used to you. Whenever you handle the crabs, you must do so very carefully.

Gentle handling can lead to good results. Sometimes you might get pinched by the crabs, but you must try not to overreact to this or you could harm the crab accidentally.

Some enthusiasts prefer to keep handling to a minimum. Just be careful when handling the crabs and things should be fine.

Final Thoughts

You now have a much better understanding of how big hermit crab tanks need to be. It’s imperative to consider the size of the crab when picking out a hermit crab habitat.

Generally, it’s best to keep a group of three or four crabs in a 10-gallon tank. A 20-gallon tank might also be appropriate.

While some suggest that hermit crabs only need one gallon of space, you must consider the fact that these creatures grow. As the hermit crabs age, they will molt, and this will increase the size of the crab.

They’ll require more space, and it makes sense to just keep the hermit crabs in a habitat that will be big enough. Also, it’s not good to overcrowd the tank with crabs where they won’t all be able to fit if they all start growing.

Make reasonable choices, and you’ll have a better experience. You should be ready to buy hermit crabs for your home now.

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