HCA: Hermit Crab Association

Hi!
I am new to hermit crabs and have learned a lot from this page already.

Set up is a ten g aquarium with heat pad on back wall (75-76 degrees F), two water dishes with fresh (bottled dechlorinated) and salt (with salt water conditioner- not instant ocean), and about 3 inches of substrate (premixed “josh’s frogs” brand which has coco fiber and playsand), and a few hidey holes and climbing materials. Three small (maybe 1/2”-3/4”?) crabs. Unknown sp. as they arent coming out during the day. Humidity is a little low 75-80% so will spray with fresh water, but I think the substrate needs to be moister (and obviously deeper). Also ordered prime and will get instant ocean to improve water situation.

Long story short, a coworker went out of town for a month and brought in the crabs. They came in a little plastic critter keeper with one small water dish and a sponge, maybe 1/4 inch substrate. So i know the current set up i described needs some work but still a massive improvement! They are now the therapy crabs and just seeing a tank in here has gotten staff and patients alike very excited haha.

So the crabs went in the new habitat and spent some time exploring before all burrowing down. Since then I know where two are because they have moved (during the night). One of the replacement shells is now missing but the third crab, old shell, and new shell are somewhere unknown. I want to fix the substrate but i dont know if i can while one crab is buried … somewhere …

Is it going to be ok buried if the substrate is a little too dry? And can I add substrate on top or do i need to wait for the crab to come up?

Thank you!

Welcome to crabbing and to the site!
Sounds like you are off to a great start!

If a crab is underground, it is best not to disturb it or dig it up. You can for sure add some more substrate on top of what is there - just don't drop it in from a height or pack it down (you don't want to accidentally collapse a tunnel or cave). HCA recommends 2 - 3 times as deep as your largest crab, you if your crabs are tiny, you may not need to add more right now, unless you want to. If the sub seems a bit dry, you can either mist it heavily and let the water soak in, or you can pour a little in around the edges. Having the top bit dry isn't usually a problem, but if all of the sub goes dry while crabs are underground, it can cause caves and tunnels to collapse.