HCA: Hermit Crab Association

Hello Ya'll,
I am a new crab owner due to classroom science habitat unit of study. In the first week of April, my 4th grade classroom acquired 2 land, PP crabs. They did fairly well in their small plastic science kit enclosure for the 2 months in the classroom. However, we are now in summer time, and I brought them home. I upgraded their habitat to a 10 gallon tank, added more coconut fibers, a log for climbing, a salt water soak area, a fresh water soak, food, a hut, and shells. Also, a new animal lamp, not my desk lamp. However, tonight I noticed one of the crabs doesn't seem to alive at all. He has lost 2 legs, is completely limp, but doesn't have any odor at all. I feel horrible. I am 99% percent sure he is dead.

I would love to learn more in order to have an amazing crabitat to return back to school with. If my smaller crab is in fact dead, how long should I leave him (currently, still in his shell, but stretched out of it), and what should I do to make sure my larger crab is well and happy? These crabs have not been active crabs, so I often get very worried when they burrow, and I do not see at all very often. I would love to add to my crabs and their habitat, but as a teacher, it has been very costly. I just feel so out of my league, and would love any support.

Hi! Welcome to HCA.

First off you will want to read through the care guides located here:

viewtopic.php?f=51&t=92457

This guide outlines all of the basic care requirements for land hermit crabs.

Each crab needs about 5-10 gallons of space, depending on size. They need a deep substrate to bury themselves in to molt. We suggest a 5:1 ratio of silica based playsand (sand box sand from a hardware store) to Eco Earth coconut fiber.

They need minimum temps of 80 degrees and humidity around 80%. They can vary slightly but I use those as a general guideline for healthy crabs. Anything below 70 in either range for a prolonged time can cause organ failure or death, but they seem to be at their happiest in the low 80's. (As with any animal you would purchase or rescue, research their natural habitat in the wild for clues as to their husbandry. We want to mimic the wild as best we can for them, as they do not breed in captivity without a Herculean effort, it's near impossible.)

Fresh and saltwater, both treated with a product to remove heavy metals and chlorine/ammonia/chloramines from tap water are necessary for healthy crabs. The saltwater needs to be marine grade that mimics the ocean's salinity. Instant Ocean is just one of the brands on the market, but it is the most commonly used and found by crabbers. It comes in a purple and white box at pet stores and the small box will last for a while if you are only using it for crabs.

Safe food- most commercial crab foods contain ingredients that are actually toxic to the crabs. In the Safe Food list linked in the care guide, you may find that you have many good snacks for your crabs in your kitchen already. You could potentially not spend a dime on any specialty crab food unless you wanted to as long as they get a varied healthy diet. They need vegetable matter/leaf litter/protein and calicum/chitin sources.

Shells need to be all natural with no paints or resins applied. Crabs pick at their shells to modify the shape to better suit their anatomy, and they eat the bits for calcium. Paints and resins are toxic as well and they also flake off after being dragged through sandy substrate, so you have little bits of paint in your crabitat.

I think I've covered the basics, heat, humidity, food, water and substrate.

Read the files in depth and feel free to follow up with any questions you may have.

Again, Welcome! and we look forward to seeing photos of your little friends in the future.

Thank you for sharing the information. I am doing my best. I did lose a crab last night, not sure why. I would think that since school has been out, I have been working on the crabitat and he became too stressed. I still have the one crab in the tank. I would love to add to that, but between all the researching and reading I have been doing I am so nervous. It seems to me that they did better with the smaller tank and less variables. I am unsure of how to attach a picture to get more specific feedback and tips.

You really did do the right thing by upgrading them to the bigger tank. They really do respond better to a larger living area - this is the same with pretty much all animals - imagine a house the size of your bedroom with no ways to get out - animals can get cramped too.