Hermit Crab Tank Setup – The Complete Guide

Hermit crabs are becoming more and more popular as domestic pets these days. They can be very low-maintenance and live for many years.

However, in order for this to be achieved, the tank in which they will live, need to be set up correctly.

To help you narrow down the vast research for different tank necessities, we are sharing the complete guide on hermit crab tank setup.


The first step towards creating the ideal home for hermit crabs is finding the perfect enclosure. That said, aquariums seem to be great solutions.

They are usually made out of glass, offering great stability to withhold heavy volumes of water, so they make an amazing option for holding the heavy substrate that hermit crabs will need.

On top of that, such material is amazing when it comes to offering isolation and maintaining stable temperature and humidity levels.

When it comes to the size, this depends a lot on the size of your hermit crabs and their colony. However, a minimal starting size is usually 10 gallons, if we take into consideration that you will accommodate about 3 small-sized hermit crabs.

For those hermits which are slightly larger, it would be better to provide them more space by placing them into a 20-gallon tank.

Finally, another important thing to consider when choosing the right enclosure is ensuring that it allows proper ventilation, as you will need a lid to keep the environmental conditions stable.


Once you find the ideal shape and size for your hermit crab enclosure, it will be time to setup the substrate correctly. There are two main things to keep in mind here: the substrate type and its depth.

Although many owners choose sand as their basic substrate because it offers a more natural look to the enclosure, we suggest selecting coconut fiber instead. Coconut fiber turns out to be more suitable for these pets during their life in captivity.

It is softer, so there is no risk of it getting inside the shell and hardening, forcing consequentially hermits to leave their home. Additionally, coconut fiber is amazing when it comes to holding humidity, which is vitally important for ensuring that your pets are able of breathing normally during their molting phase.

On top of that, such substrate type is great at withholding bad odors.

The depth of the substrate, again, depends on the size of your hermit crabs. A good thumb rule to apply is ensuring that there is enough depth to cover the shell of your largest crab three times.

That said, small hermits will need around 4 inches of substrate across their tank, while larger specimens will require at least 6.

And finally, it is suggestable to gradually setup different depths of the substrate, starting from one side of the tank with lower levels and finishing to the opposite side with deeper levels.

That way, there will be enough space for them to be buried underground as well as enough space for them to play on the surface. And there will be fewer water spill-outs from their dishes, too.

Food & Water Bowls

As opposed to many other pets which usually require food and a fresh bowl, hermit crabs are a funny exception as they demand two water dishes besides the one for food. Indeed, they need both fresh and saltwater in order to survive.

Freshwater is essential to keep them hydrated and they will use it for drinking purposes. Saltwater is necessary because they use it to keep their shells hydrated, which is just as important for them to thrive.

Both water options need to be de-chlorinated first and they need to be offered in separate dishes. When choosing such containers, you can either pick them up from pet stores or craft your own variations.

Whichever option you choose, it is important to keep them shallow and easily accessible. Although hermit crabs are born in the ocean, they later adapt to land life and can drown if being submerged in water.

The food dish you choose has to be easy to remove on a daily basis for cleaning purposes.


Next, it is time for decoration! You can play as much as you like here, as your new pets will be happy when seeing lots of hiding and climbing places.

Hermit crabs are extremely active once they adjust to a new environment. They like climbing, exploring, digging and even throwing things around.

Make sure to provide them plenty of branches, tiny homes, hiding places and plants. You can choose appropriate decorations from pet stores or use some natural variations.

They will happily accept everything you provide them with. The important thing is to carefully disinfect any items you wish to place in their enclosure first.

When it comes to plants, some owners prefer having real ones as opposed to plastic options. This is absolutely safe when it comes to hermit crabs, but please be prepared of having to re-plant them quite often. Any live plant will quickly be eaten up by your pets.

Temperature & Humidity

Hermit crabs require high humidity and warm temperature to thrive, so this is certainly one of the most basic requirements when setting up their enclosure.

Daily temperature levels need to be anywhere between 75- and 85-degrees Fahrenheit, while those during nighttime can be somehow lower, between 65- and 75-degrees Fahrenheit.

For small tanks as those of 10 or 20 gallons, these levels can easily be maintained with the help of simple under-tank heaters. However, make sure to place them on the side glass rather than the bottom, to avoid your pets getting burnt when burying deep in the substrate.

Hermit crabs are not able of creating their own body warmth but they need to absorb it from the environment instead, so please make sure their temperature levels are always stable by constantly monitoring the thermometer you will set in the middle of the tank.

Humidity is just as important for these creatures to survive. Indeed, they are not able of collecting oxygen from water or from the air. Instead, they require extremely humid air for being able to breathe through their modified gills.

In order to do that, humidity has to be around 75 or 85% at all times. There are various ways to obtain that, from fully-automated humidifiers to appropriate foggers, but simple manual misting with de-chlorinated water will do absolutely fine for smaller tanks.

As long as you have a hygrometer in the middle of your tank and you constantly monitor it, there is nothing to worry about.

Adding to appropriate temperature and humidity, it is recommendable to also set a simple light bulb at the top of the tank.

This will ensure your pets are getting the daily portion of sunshine they deserve. Some owners like even adding a night bulb to observe their pets exploring around, but this one is not essential.

Diet & Nutrition

As for any other living being, diet is central to health. Hermit crabs are greatly easy to please here, as you will basically need to follow two guidance rules: one is to choose high-quality commercial pellets as their basic meals, and the other is to add a variety of different fresh foods to their pellet meals.

Hermit crabs are omnivorous scavengers, which makes them happy eaters of basically anything. Besides their pellets, you can offer them either vegetables, fruit, fish, or cooked meat. Great treats can be occasional nuts as well as unsalted crackers, but even grass.

Besides their regular daily meals, it is important to ensure they are getting enough calcium and vitamins. This is extremely important with hermit crabs because their exoskeletons depend on the right calcium intake.

You can choose commercial powder products, but there are also great natural ways of providing them calcium, such as boiled eggshells or cuttlebone.


Shells make a super-important amenity in any hermit crab enclosure. They are constantly in the research for the next perfectly fitting shell to inhabit, so it is important to provide at least three of those for each of your hermit pets. This is especially important during their molting phase.

Avoid heavily colored shells as these can be dangerous for your pets, and always try selecting those that are slightly larger from the shells where they currently live in. And of course, remember to properly disinfect every shell before placing it into the enclosure.

Wrapping Up

Setting up the perfect enclosure for hermit crabs may seem like a big task for first-time owners. And indeed, there are many things to consider and to be careful about. However, once this is properly achieved, your pets will become extremely low-maintenance.

Providing them with fresh water and food, scooping up visible waste and making sure the environmental conditions are met is basically all you will need to do on a regular basis.

A proper tank environment is essential to avoid complications and various adjustments afterward, so try getting it as ideal as possible from the very first time. This video may greatly help you, too:

avatar Noah
I’m Noah, chief editor at VIVO Pets and the proud owner of a playful, energetic husky (Max). I’ve been a volunteer at Rex Animal Rescue for over 2 years. I love learning and writing about different animals that can be kept as pets. read more...

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