Do hermit crabs need certain sand?

What Kind of Sand Is Safe for Hermit Crabs?

Last Updated on: 14th October 2023, 10:48 pm

Most kinds of sand are hermit crab-safe, except calcium sand (vita sand or reptile sand). It solidifies when exposed to moisture, which can trap or suffocate pet hermit crabs.

Also, avoid fine sand or sand with poor moisture retention to keep hermit crabs safe.

Suitable alternatives are all-purpose sand, beach sand, and aquarium sand. To improve the water-retaining qualities, coconut fiber can be combined with sand.

What Sand Is Bad for Hermit Crabs?

No sand is toxic, but bacteria, debris, and chemicals can be harmful. The risks include:

  • Dirty sand. A hermit crab’s enclosure must be combed and cleared of debris. Bacteria or sharp objects pose a health risk, especially when a hermit crab is molting.
  • Fine sand. Hermit crabs may find it hard to burrow into overly fine sand, leaving them stressed and exposed. Also, fine sand can prevent airflow or trap hermit crabs, leading to suffocation.
  • High calcium sand. This sand doesn’t allow moisture or safe burrowing.

As long as the sand isn’t dirty, full of debris, overly fine, or high in calcium, it’s suitable.

Can You Use Regular Sand for Hermit Crabs?

Hermit crabs can adapt to most kinds of sand, including regular sand. However, traditional sand is only acceptable when the following applies:

Facilitates Burrowing

Hermit crabs are natural borrowers because this behavior allows them to rest and gain protection.

The sand must be easy to dig through and not prone to cave-ins. Choose sand with more moisture content that isn’t too coarse or fine.

This is important because hermit crabs are nocturnal creatures. Hermit crabs are most active at night, so they’re more likely to be burrowed underground during the day.

Burrowing is a form of defense. Without their shells, hermit crabs are vulnerable to predators and the sun’s UV rays, so they often bury themselves under substrate for protection.

Water Retention

To tunnel through their living environment, hermit crabs need moist sand. Specifically, it must hold its shape and have a sandcastle-like consistency.

Hermit crabs can’t tunnel through hardened earth, especially when molting.

Protection is essential when molting because hermit crabs will shed their exoskeleton. Until they grow a new exoskeleton, hermit crabs are most vulnerable.

They can’t move while their new shells harden, leaving them at the mercy of the elements.

According to the New Zealand Journal of Marine and Freshwater Research, molting hermit crabs will seek the safest place to molt. This is why burrowing often signifies that a hermit crab is about to shed.


Most importantly, hermit crabs need clean sand because they can endure health problems if left in a waste-filled environment.

This means you must deep clean the enclosure once every 3-4 weeks. The sand must be changed entirely out in intervals to prevent excessive bacteria.

Ensure the new sand contains no sharp objects and is sanitized.

How do you sterilize sand for hermit crabs?

Best Kind of Sand for Hermit Crabs

Not posing a direct danger to your hermit crab doesn’t mean that all sands are equal. We’ll explore the kinds of sand that hermit crabs will enjoy the most:

All Purpose Sand (Quikrete)

All-purpose sand is ideal as it has the right texture and size. It also comes pre-washed, making it a safer choice. While it may seem too industrial for hermit crabs, it’s safe.

All-purpose sand is washed and coarse, making it clean and water-retaining. You can get a 50-pound bag of Quikrete at your local hardware store.

Beach Sand

Beach sand may not be as accessible to most people as a bag of Quikrete. However, if you live near a beach or travel to the beach regularly, it’s ideal. However, there are caveats.

When using beach sand, always subject it to the following routine:

Check The Texture

Beach sand that’s too fine won’t be good for hermit crabs, as fine sand makes burrowing difficult, potentially causing suffocation. Instead, choose sand that’s coarse with larger grains.

Remove Debris

Beach sand (also known as wild sand) has no standards for cleanliness.

If you gather it from your local shoreline, you may find it’s full of debris, like glass. Even on cleaner beaches, it’ll contain pebbles, cracked shells, and corals, which can cause injury.

Comb The Sand

Before putting the substrate into a hermit crab’s tank, comb through the sand with a sifter.

The goal is to remove the tiny debris you missed on the first sweep, including small glass shards and sharp coral pieces. This is especially important when hermit crabs enter the molting stage.

Bake The Sand

Bacteria or pollutants found can kill hermit crabs. Wash the sand, dry it, and bake it in the oven.

Aquarium Sand

Aquarium sand usually comes in various colors, from black to pink.

Aquarium sand may also have special features to make it more convenient for aquarists. For example, it may help remove waste or maintain a pH balance.

If you do opt for aquarium sand, choose the basic kinds.

Play Sand

Play sand is the same material as beach sand, but it’s been washed, treated, and shipped out. Regulations ensure that the sand stays clean and safe throughout this process.

It’s safe for hermit crabs, but be careful about the vendors. The quality will largely depend on the brand, as some are stricter about cleaning than others.

Sand Mixed with Soil

Sand is a good choice, but mixing it with other substrates broadens its advantages.

For example, soil-based substrates, like coconut fiber, can improve a hermit crab’s diet, traction, and cleanliness of its environment.

After all, hermit crabs are used to multiple terrains on beaches and shorelines. You’ll make them feel more at home by providing diverse terrain.

Use a ratio of 5 parts sand to 1 part coconut fiber. Used together, this mix is superior to a coconut fiber or sand substrate.

Coconut fiber absorbs water well, allowing the substrate to retain moisture. Sand can fill the spaces in coconut fiber, making digging and burrowing significantly easier.

A common choice is Eco Earth coconut fiber, made from the husks of coconuts.

Can You Use Reptile Sand For Hermit Crabs?

Reptile sand (vita sand or calcium sand) may seem appealing.

However, there are negatives to reptile sand, namely the calcium itself, which is excessive in most reptile substrates. Calcium sand is made from calcium carbonate.

Advantages of Calcium Sand

Calcium sand may seem ideal for hermit crabs because:

  • It’s often marketed to be used for hermit crabs.
  • Hermit crabs need calcium in their diet to grow and stay healthy. According to the International Congress Series, hermit crabs naturally prefer a calcium-rich diet.
  • Calcium sand comes in many colors, making a tank look more vibrant.
  • Some calcium sands are fortified with vitamins and minerals.
  • Calcium sand makes cleaning the tank easier as it hardens around waste materials.

Disadvantages of Calcium Sand

Unfortunately, calcium sand isn’t ideal for hermit crabs because:

  • Calcium-based reptile sand is more expensive; all-purpose sand is cheaper.
  • Most reptiles don’t need wet environments. So, their sand is kept dry, allowing it to stick to waste material for easy cleaning. However, wet calcium sand dries and hardens, making burrowing difficult.
  • It can collapse underground tunnels or trap hermit crabs that have burrowed underground.
  • Reptile sand is too powdery, which makes digging and climbing difficult.
  • Hermit crabs may get trapped and be unable to draw air through the grains, leading to suffocation.

How To Make Hermit Crab Substrate

You can save money on pre-packaged hermit crab sand by making your own. DIY hermit crab substrate involves blending sand or mixing substrates.

For example, you can blend all-purpose sand with coconut fibers. You can also mix beach and aquarium sand to save money while enjoying the unique colors.

Here’s how to prepare your hermit crab sand:

Substrate Depth

Too-shallow substrate makes it hard for hermit crabs to burrow. Likewise, a substrate that’s too deep can be difficult to clean. Instead, determine the ideal depth of the sand:

  • Take the measurements of the largest hermit crab.
  • The depth of sand will need to be 3-4 times this size.

This will give all hermit crabs, including the largest, enough space to molt.

Do hermit crabs need dry sand or wet sand?

Tank Size

Measure out the size of the tank. Remember, hermit crabs should be kept in groups.

So, there should be at least 10 gallons of space per pair of hermit crabs. You should keep an area free of objects where hermit crabs can run to expend energy.

Note that the depth of sand should be uniform throughout the whole tank. Subtract any objects you embed into the substrate, like pools of water and pots.

Examine Your Sand

Even if you have store-bought sand, ensure it’s free of dirt, debris, and foreign materials. Also, check for bugs and mildew; if you find any, the sand must be replaced.

While all commercially sold bags are packaged and sealed, old bags can still be compromised.

Wash The Sand

Once the sand is free of foreign material, it’s time to clean the mixture:

  1. Pour water over the sand.
  2. Stir it with a long wooden spoon or any other non-metal mixing tool.
  3. Let the sand settle for a minute, and tip out the water.
  4. Repeat this process. You’ll need to rinse the sand 5 times until the water runs clear.

Once the water has run clear, it’s time to heat the sand. This will remove bacteria, mold, fungi, and microorganisms. To do this, you can bake or boil the sand.

To bake the sand:

  • Pour the still-wet sand into a baking tray or a large glass pan.
  • Bake for 20 minutes at 200 degrees Fahrenheit.

To boil the sand:

  • Place it in a pot and add enough water to submerge the sand.
  • Cover the pot and let it boil for about 20 minutes.

Mix To The Right Consistency

Add water until your sand reaches the right consistency, which will be sandcastle-like and able to hold its shape. Hermit crabs can safely burrow under the substrate without cave-ins.

During this step, use dechlorinated water, as hermit crabs are sensitive to chlorine. You can do this by:

  1. Getting bottled spring water.
  2. Boil some tap water for 20 minutes.
  3. Adding dechlorinating water treatment drops.

What’s the best sand for hermit crabs? It comes down to the following:

  • Availability. Quikrete may be what you can find most easily.
  • Budget. Gathering sand from the beach may be cost-effective, but clean it throughly.
  • Aesthetic preferences. If you prefer brighter colors, aquarium sand may look nice.

You can create a good home for hermit crabs with a suitable sand-based substrate.