Welcome to The Crabstreet Journal

Login or Signup to meet new friends, find out what's going on, and connect with others on the site.

Sign Up Now

Registering for this site is easy. Just fill in the fields on the registration page and we'll get a new account set up for you in no time.

Forgot Your Password?

A new password will be e-mailed to you.

Member Login

Profile photo of Stacy


FAQ How do I create and maintain humidity in my crabitat?

October 16, 2012 in FAQ

Answered by Stacy Griffith
The first step to creating and maintaining humidity in your tank, is a good lid. A screen lid alone is not sufficient. A glass/plexiglass/lexan lid, cut to fit is the best option. In the short term, you can use plastic wrap over the screen lid. A small opening should be left for air exchange. The size of the opening may have to be adjusted until you find the right spot to maintain your humidity. Plexiglass/lexan can be purchased at most hardware stores and be cut to size for free.

Soaking your substrate is not the way to raise humidity. SLIGHTLY moistening the substrate above the UTH is okay.

Water Dishes:

Your tank should have two types of water bowls, salt and fresh. Use bowls that are wide and shallow. This increased surface area will create more humidity. Water dishes may be placed slightly over your UTH (under the tank heater) or beneath your overhead light to produce additional humidity.

Natural moss:

Crabs love moss! Placing moss anywhere in your tank and keeping it damp will raise your humidity. Replace as needed. You can buy moss at the pet store in bags or compressed bricks. Look for Hiawatha or sheet moss, terrarium or frog moss, natural and undyed.

What Moss is Safe?
Is Beaked moss safe?
Is Sphagnum moss safe
Is Cypress safe?
Don’t Forget the Moss


Repti foggers can be placed in the tank to create humidity as well. They cost around $30.00 and can be purchased at your pet store. You can make your own with the directions here: Homemade Humidifier

Spidtat/Travis’ review of his Tropicair Reptile Humidifier


Sponges were once considered a staple in the hermit crab tank but there are better solutions to the humidity issue. Sponges placed in the fresh water will raise humidity. Sponges should be changed out daily, sterilized and replaced with already sterilized sponges. Sponges placed in the salt water will become nasty fast. Due to the upkeep of sponges it’s easier to go with moss.

If you have just discovered that your crabs need humidity and you are not able to fix the problem immediately you can place a wet towel over the tank. The towel must be kept wet and this is not a long term solution. You can also mist the tank with dechlorinated water. This is not a long term solution either as the humidity will fluctuate too much between mistings to be suitable.

Originally posted at All Things Crabby The Hermit Crab Care Blog

Comments are closed.

%d bloggers like this: