how to treat mites on hermit crabs

How To Get Rid of Mites on Hermit Crabs Safely

Last Updated on October 4, 2023 by Joanne Harper

Mites congregate around hermit crabs’ skin, eyes, and antennae. The only way to kill mites attached to a hermit crab is through bathing in saline water and deep cleaning the tank.

Mites are tiny arachnids that thrive in warm and humid conditions. A hermit crab living environment will be particularly welcoming to mites, so you must prevent the tank from becoming infested.

Regular cleaning is the most effective way to prevent mites from gaining a foothold. Remove uneaten food and feces, clean mold off the walls, and change the substrate whenever the need arises.

Never use an insecticide or mite killer because this will also be fatal for hermit crabs.

Do Hermit Crabs Get Mites?

Various insects and arachnids are found in the substrate, especially in soil over sand.

The Journal of Experimental Marine Biology and Ecology stated that up to 15 different types of mites may attach themselves to hermit crabs. The most common mites are as follows:

Acarus siro:AKA the ‘flour mite,’ this pest is attracted to uneaten food.
Demodex folliculorum:Follicle mites can live on human skin, which means they may enter a hermit crab tank during handling or cleaning.
Dermatophagoides pteronyssinus:The common house dust mite is the most common hermit crab pest.
Liponyssoides sanuineus:The mouse mite is often found on rodents entering the home.
Oribatida:Also known as moss mites, these are very common in soil.
Psocoptera:Booklice are commonly found feeding on paper and binding glue.
Sarcoptes scabiei:The ‘itch mite’ is responsible for scabies, but this zoonotic mite is rare in hermit crab enclosures.
Tyrophagus putrescentiae:They are known as the mold mite because they consume mildew.

Check your hermit crabs regularly for any sign of mites, taking action to remove an infestation.

What Do Mites Look Like on a Hermit Crab?

Mites usually resemble tiny red, white, or black clusters on your hermit crab’s skin.

Pay particular attention to the legs, eyestalks, antennae, and abdomen. You will likely need a magnifying glass to see and identify mites.

If you notice these color markings, hold your gaze for a moment or two. If the color clusters start to move, they’re almost certainly mites.

Can Mites Kill Hermit Crabs?

Almost all mites will be an annoyance to hermit crabs. Like all animals, hermit crabs can be driven to distraction by mites. These tiny bugs will bite and irritate hermit crab skin and eyes, leaving them desperate to relieve discomfort.

The stress and discomfort caused by a parasitic infestation can make hermit crabs behave erratically, including displays of aggression or the shedding of limbs. This can be fatal if left unmanaged.

Some mites are more directly harmful to hermit crabs than others, as they carry bacterial disease and other infections. As it’s difficult for anybody outside of an entomologist to determine different mite species, all should be considered a hazard.

how to get mites off hermit crabs

Are Hermit Crab Mites Harmful to Humans?

The mites found in hermit crab enclosures are so small they’re disinterested in humans. You’re unlikely to become sick through contact with hermit crab mites.

If the mites in a hermit crab enclosure make their way into your home, they can still be problematic.

Dust mites, grain mites, and booklice can destroy your possessions or make food inedible. Hermit crab mites aren’t zoonotic, but neither are they harmless.

What Causes Hermit Crab Mites?

Mites are attracted to warm, humid conditions, which makes a hermit crab enclosure an ideal location.

Mites will also feed on leftover food, moss, and other natural elements of a hermit crab tank. Unsanitary conditions will always place your hermit crabs at greater risk of a mite infestation.

How To Prevent Hermit Crab Mites

While it’s impossible to guarantee you’ll never find mites in a hermit crab enclosure, you can take precautions to minimize the risk of infestation, including:

  • Ensuring a habitat is airtight, with no cracks in the walls or roof.
  • Spot clean daily, emphasizing removing uneaten food and clearing any growth.
  • Purchasing organic fruits and vegetables and washing them before serving.
  • Sanitize any substrate, decoration, or toy before placing it in a hermit crab tank.
  • Deep cleaning regularly, ideally once every two months.

These steps will go some way to reducing the likelihood of mites attaching themselves to your hermit crabs. You’ll likely find parasites in a tank and must know how to eliminate them.

How To Treat Mites on Hermit Crabs

Prevention of mites is recommended, but almost all hermit crabs will still experience an infestation at some time. Understanding how to eliminate mites is a critical component of hermit crab care.

Never use a commercial mite-killing spray in a hermit crab enclosure or around the home. These insecticides will be lethal to hermit crabs and parasites, so mite infestations must be managed by hand.

Start by getting in a second habitat if you don’t already have one. This needs to be large enough to host all hermit crabs eventually, so it needs to be the same size or bigger than their primary tank.

Fill this tank with enough substrate, toys, entertainment, and water. You can now treat your hermit crabs for mite infestations one by one. Once your hermit crabs are mite-free, move them to the new enclosure while you deep-clean their primary residence.


Bathing is the only safe way to remove mites from a hermit crab. Most hermit crabs with a mite infestation will bathe themselves to self-soothe. You may need to step up this hygiene program.

Ensure a hermit crab habitat has at least two pools of room-temperature saline water.

Pest Management Science confirms that sodium is an effective mite-killer. This saline water must be purchased from a pet store, as table salt contains toxic iodine.

Encourage your hermit crabs to bathe in saltwater multiple times per day. This will go some way to relieving the discomfort associated with mites.

Another effective remedy is to fill a bowl with room-temperature water and apply marine salt.

This water must be bottled or purified by a water filter; avoid tap water because it contains chlorine and heavy metals that kill hermit crabs.

Gently place the infested hermit crab in this water and allow it to submerge fully. Leave the hermit crab underwater for 10 minutes, then return it to the surface. This soak and absorption of salt should be long enough to kill any remaining mites.

By now, your hermit crab should be clear of infestation. Dab it dry with paper towels and place the hermit crab in the new, empty enclosure. Now, repeat this bathing process with your other hermit crabs.

Encourage a Change of Shell

After bathing, your hermit crab should be clear of any mites.

Also, the new habitat you have placed the hermit crab in should be clean. Stubborn mite eggs may have survived the sodium exposure and remain in the shell, so it’s best to encourage a change.

Ensure that you have non-painted shells in the new habitat that are the size and shape of your hermit crab’s existing choice. Place these in clear sight of your hermit crab.

If your hermit crab associates their recent discomfort with their shell, it may change shells willingly. It should be comparatively simple for a hermit crab to wriggle out of a shell straight after a bath. With luck, it’ll immediately try a new shell for size.

If your hermit crab doesn’t immediately show interest in changing shells, don’t physically force it. If you attempt to drag a hermit crab out of its shell, it’ll panic and pinch before retreating and hiding.

Make a new shell appealing through scent. Ensure plenty of saline water and humidity in this new enclosure to stimulate a hermit crab’s sense of smell and apply a sweet food, like a dab of jelly, to the new shell. The hermit crab will find its interest piqued and consider a change.

can mites kill hermit crabs?

Encourage Molting

After battling a mite infestation, your hermit crab may be keen to molt its exoskeleton completely and grow a replacement. This will remove any lingering traces of the mites and regrow any limbs severed in distress during the infestation.

Most hermit crabs molt every 18 months by default. If a hermit crab that experienced a mite infestation is scheduled to molt, it may attempt to bring this forward.

Encourage hermit crabs to molt by minimizing light exposure. Just be aware that, as per Marine Environmental Research, near-constant darkness can lead to unruly behavior in hermit crabs – and attract more mites, as they love poor lighting.

How to Get Rid of Mites in a Hermit Crab Tank

Once your hermit crabs are cleansed of mites and safely housed in a second tank, you must work on cleaning the primary residence.

Start by completely emptying the habitat; remove all decorations and substrate. Once the tank is empty, use an aquarium vacuum to suck up any mites that managed to remain in the tank.

Once the tank is empty and vacuumed, clean the floor, walls, and roof. You can use water and white vinegar or water and bleach.

The Journal of Crustacean Biology warns that the latter can cause symptoms comparable to black gill disease, so dilute it heavily to remove all traces.

Once the tank has been cleaned, provisionally dry it with a hairdryer, then leave the habitat outside to dry in the sun. The habitat should be left out for at least 24 hours – longer during colder months, as it needs to be completely dry before the next steps.

While your tank is drying outside, sanitize the contents. Substrate should be thrown away, as mites and their eggs will be within. Don’t try to bake and recycle it; start with a new substrate.

Any wooden decorations should be baked in the oven at 300°F and left outside to dry (weather pending.) Spare shells and water dishes should be boiled and left to cool before reapplying to the habitat.

When everything is dry and sanitized, lay new substrate into the habitat and return your hermit crabs to their primary enclosure. Both hermit crabs and terrain will not be devoid of mites.

Mites are a fact of life for most hermit crabs, but this doesn’t mean they can be ignored.

For hermit crabs, a mite infestation can be extremely uncomfortable, even deadly. Take all necessary steps to prevent parasites from gaining a foothold in an enclosure.