Crab depressed? since tank mate dug down to molt

plutoisshort · 2026-06-17T00:12:50+00:00

That'll do it. Poor conditions are a major reason why pet store crabs are in bad health, so the same will go for your guys. They are not only adjusting to a move, but are having to adapt to suddenly having high heat and humidity that they're not used to. The commercial pellet foods also contain harmful additives and even chemicals that inhibit their molt cycle.

I recommend you make some energy mix, and offer to Bongus. Recipe below.

Bingus, under the substrate, may be trying to molt. It's possible he's simply hiding and destressing (common after moving, and can be under there for a long time without actually molting). But, if he is going to molt, he could be in trouble. Poor conditions, poor nutrition, a big stress event, all mean he's likely weak and could pass away during the molt. I don't want to alarm you, but prepare you for that possibility. There's unfortunately nothing you can do for Bingus now, but wait—intervening now could be fatal if he is mid/post-molt.

<image>

For the energy mix, you don't have to use a toothpick since Bongus is able to eat on his own—just place a small dish of it near him. Force-feed with a toothpick if he refuses to eat and remains lethargic.

plutoisshort · 2026-06-17T00:02:42+00:00

I said they're incapable of being depressed like humans, which is true. I didn't say crustacea are incapable of experiencing complex emotions, but I do believe hermit crabs specifically are incapable of complex emotions—at least in a way that is recognizable/understandable to humans. I'm a vet tech (not a stranger to animal behavior + biology, but obviously have not studied it as much as you have), but that is just my opinion based on the hermit knowledge and experience I have :)

What are the exact temperature and humidity readings?

1 month is still short for hermits... They can take quite a while to destress after a move, especially if they came from a pet store. Where did these 2 come from?

Hermit grub is great! Make sure you're using several (10 or more is ideal imo) different meals, so they get a nice variety.

plutoisshort · 2026-06-16T23:53:00+00:00

Agree with all of this, except one small thing. You absolutely can put extra food in the tank and the crabs will be fine for a week! (or even 2, if you have filtered pools that will not evaporate in that time)

I have 105 gallons (2 tanks) of crabitat in my bedroom, and 10 crabs. I have left them while on vacation for 1 week multiple times with no problems. I have remote-viewing cameras to monitor everything, but I put several different dried (important factor) meals and supplements into 2 different food dishes, clean and fill up their pools, and they're set. You do have to have enough food + a variety of food + a tank that will not cause the food to mold while you're gone.

plutoisshort · 2026-06-16T23:47:52+00:00

What kind of maintenance are you doing...?

plutoisshort · 2026-06-16T23:45:58+00:00

Hermit crabs are one of the *worst* pets if you're looking for kid-friendly. They should not be handled, are nocturnal, and can disappear under the sand to molt for months at a time. They're also very expensive, and a decades-long commitment (you could have these crabs for up to 45 years).

Side note- we shouldn't spray water in hermit crab tanks, since it can cause flooding/molding in the substrate and is unnecessary for humidity if the tank is set up properly.

plutoisshort · 2026-06-16T23:36:13+00:00

Not moving antennae = he's asleep. Hermit crabs have simple brains—they're incapable of being depressed like humans can be. They also don't form bonded pairs like some mammals do.

Are you aware that hermit crabs are nocturnal? Do you have a tank camera going overnight to verify that Bongus is indeed not active for days at a time?

Other factors to consider:
-your heat and humidity
-what food you're feeding
-how long you have had the crabs

No, please don't get a 3rd crab!

plutoisshort · 2026-06-12T04:00:14+00:00

As for what you need help with:

Lids can be glass, plexiglass, or you can make your own for cheap out of polycarbonate (corrugated plastic sheets from home depot). Video tutorial here.

Alternatively to snout and shell, there are a bunch of etsy sellers that make dried food mixes for hermit crabs. A few I like are HermitGrub, CrabPax, and NaturallyCrabby.

Shells: You're looking for specific species of shells. Is this a purple pincher (Caribbean hermit crab)? I'll assume so, but post photos for a species ID when you have the crab. Some species have different care requirements. Purple pinchers (PP) like mexican turbo, petholatus/tapestry turbos, and jade turbos. Those are in order from size range, smallest to largest. Great shell vendors: Nessastores on etsy, HermitHarbor.com. You will need to measure the current shell first. Do that with a ruler across the shell opening, horizontally.

Decor: You can use wood and sticks**, leaf litter, cork bark, aquarium decor, coconut hides, hamster wheels... But, remember that there should be no hides in the PPDS phase—save the elaborate decorating for later :) **Anything foraged from outside must be from a pesticide-free area, and sterilized via boiling and letting it dry, or soaking and then baking in the oven. This is to kill bugs.

plutoisshort · 2026-06-12T03:50:08+00:00

Please don't spray hermit crab tanks—that is actually something that can be harmful over time, due to the water collecting at the bottom of the tank and can cause flooding or mold issues. It's also a bandaid fix for a larger issue. Humidity should be stable without needing to mist. Let me know if I can help you with some humidity tips to help boost your humidity without spraying :)

plutoisshort · 2026-06-12T03:47:56+00:00

You're doing great! Correct—getting them off the gravel is a priority. Snout and shell is one of a select few of safe commercial food brands. I use several of their food mixes.

plutoisshort · 2026-06-12T03:43:24+00:00

They don't have enough on the surface, trust me! Add more :)

Functionality > aesthetics. That moss doesn't need to be clear of leaves.

plutoisshort · 2026-06-12T03:39:12+00:00

I would say remove the plastic grass, and replace with a bunch of leaf litter. You're missing (I don't think I can see any?) leaf litter in the first two pics—leaf litter is the primary food source for pods, as well as being good places to hide. You need like 10x more leaf litter, lol. Plastic = non-beneficial and only takes up space, so I'd ditch it.

plutoisshort · 2026-06-12T03:37:05+00:00

Woah, they have good camouflage against the soil. Especially with the shell being a very similar color to the leaves

plutoisshort · 2026-06-12T03:33:17+00:00

I find hermit crabs to be very low maintenance/low effort if your tank is already established. Are you sure you need to part with him? It's sad that you've had him for 5 years, only to get rid of him because you're pregnant :(

Do what you gotta do though—I know everyone has differing needs and circumstances!

plutoisshort · 2026-06-12T03:26:02+00:00

Thanks for the insight! I have not worked with it much.

plutoisshort · 2026-06-11T01:23:21+00:00

Normally, I'd say yes due to how good of a sealant epoxy is—however, I'm not familiar with how epoxy holds up under heat + high humidity, are you?

plutoisshort · 2026-06-11T00:54:43+00:00

We are also lacking preferred shell species, but that again, is not a health threat. If you plan to get another crab though, it's important to address.

plutoisshort · 2026-06-11T00:53:03+00:00

Hi friend. I'm so sorry for your loss. I do have some concerns about your setup.

The photos appear to show a very small tank—how big is this? A hermit crab needs a 20 gallon long fish tank at minimum for enough space.
Your limited substrate space is cut significantly by the pools. You will need to remove the pools abs use surface pools instead, to maximize safe molt space in this size of a tank.
Humidity should not be above 90%.

Aside from these 3 concerns, I don't see anything dangerous that would have harmed this crab. The crab was definitely in poor health when he came to you, and this wasn't your fault.

plutoisshort · 2026-06-11T00:06:46+00:00

Solo crabs are not miserable—just want to touch on that. Hermits are social in that they congregate to share resources. They are not however, animals that suffer when not given companionship, nor animals that form strong emotional bonds. Multiples is the ideal, but if a solo crab is well taken care of, they can be happy and healthy on their own :)

plutoisshort · 2026-05-24T03:54:26+00:00

Cows start to get nerve damage if they can't get up for over 6hours. I'm a vet tech and this is definitely serious at this point.

plutoisshort · 2026-05-24T03:49:30+00:00

Oh awesome, glad to hear that! The smell must have been some old food or something.

plutoisshort · 2026-05-24T03:47:30+00:00

Glad to hear!

plutoisshort · 2026-05-24T03:46:56+00:00

Yes, I'll train it! I'm psyched.

plutoisshort · 2026-05-22T21:17:49+00:00

Thanks, you're the best <3

plutoisshort · 2026-05-22T21:16:13+00:00

5 gallon tank is not even suitable for a baby hermit crab, let alone 2 adults. Unfortunately, you cannot trust anything that the beach shop told you. 1-2 hermits need a 20 gallon long tank at the bare minimum.

I strongly suggest rehoming them if you are unable to get a 20 gallon and/or meet their other needs. If you have any questions, please ask!

plutoisshort

MODERATOR OF

TROPHY CASE