HCA: Hermit Crab Association

Hi! I'm gonna fire a million questions at you! So i'm making a hermit crab home and its 10 gallons. I'm planning on getting 3 quarter sized crabs or smaller. Is that ok? Or can i have more? I read the more the merrier.
Also you don't have to run me down on basics, I read a million articles. I'f you have anything that I might not know, go ahead though! I want to get a good heating system, that might be low on price? Any suggestions? Also i had a single hermit crab before i was informed so i'm in a passionate mode to save hermit crabs, not end them! Also, it was a childhood dream of mine.
But anyway, Is shells from the beach a good thing instead of buying a cuttlebone? AND also i see stuff like "feed the hermit crabs corn!" But isnt corn a starchy veggie? Can't the crabs not have potatoes because of that?
Can you use actual sea water from a sound for saltwater? And can you just mix sea salt in water for saltwater?
And is filtered water freshwater? I don't think that takes the chlorine out...
Don't hermit crabs need to walk? They can walk 9 miles in a night right? So should i buy them a hamster saucer?
Stay tuned for season 2 because I know I will have more questions!!!

Welcome to the site!
If you haven't already looked at our care sheet, I recommend starting with the 'basics' one, which will answer many of your questions. It also has a picture of a basic tank, which is actually a ten gallon:

viewtopic.php?f=120&t=119273

How many crabs you can have safely share a tank will depend on the size of the crabs. I started with two tiny crabs in a ten gallon for 2-3 years, then upgraded to a 20 gallon for another 2-3 years, then upgraded to a 45 gallon for a maybe 7 or 8 years, and now have a 65 gallon (one of my crabs who was now a jumbo passed away last year, and I added two more tiny crabs to the 65 gallon). Here is our care sheet about numbers and sizes:

viewtopic.php?f=26&t=92541

Do not take shells from beaches.

Here is everything you need to know about nutrition:

viewtopic.php?f=25&t=92554

Do not use water from the ocean, there are too many contaminants and bacteria etc. Filtering does not remove chlorine. You need a dechlorinator and then marine salt. Here is everything you need to know about water:

viewtopic.php?f=127&t=92553

You may not have room for a hamster saucer in a 10 gallon. I have never had one.

I have never used a hamster saucer either. Three quarter sized crabs is good. Mine have grown so fast. I have two medium sized crabs in a 10 gallon. I am getting a heat pad too. Get them from reptile basics or the bean farm. I am getting a 6x17 for my 10 gallon (Put it on the back of the tank. If it isn't it could mess with molting crabs and you would have hot sand.). You will probably only need to use it in the winter months. Sea salt mixed in water can be bad for them. A lot of people buy Instant Ocean and use it for crabs (It is intended for fish). It's cheap and makes a TON of saltwater. Crabs do a lot of their walking while climbing. They are super strong.

ChonkyCrabsLover wrote: ↑

Thu Aug 22, 2024 11:10 am

I have never used a hamster saucer either. Three quarter sized crabs is good. Mine have grown so fast. I have two medium sized crabs in a 10 gallon. I am getting a heat pad too. Get them from reptile basics or the bean farm. I am getting a 6x17 for my 10 gallon (Put it on the back of the tank. If it isn't it could mess with molting crabs and you would have hot sand.). You will probably only need to use it in the winter months. Sea salt mixed in water can be bad for them. A lot of people buy Instant Ocean and use it for crabs (It is intended for fish). It's cheap and makes a TON of saltwater. Crabs do a lot of their walking while climbing. They are super strong.

People who use air conditioning will often use a heat source all year round! And the reason we don't put the UTH under the tank is not because it will cause hot spots in the sand, it is because it is a fire hazard.

Hi!
I have just 1 crab that is 21½ years old (I got it may 2003, not sure how old it was when I got it but it was small). Started with 4 and this crab has been resilient to say the least lol. It's in a 29gal tank.
Here is my advice based on my experience:

Be prepared for a long term commitment.
Regardless of the type of crabs you have:
Give them 2 dishes of water, 1 fresh and 1 salt water ( I keep 2 jugs of distilled water on hand, one regular distilled water and another gallon jug of distilled water that has a half cup of "instant ocean" mixed in)
Water dishes deep enough for the crabs to submerge halfway, but shallow enough for it to be able to exit the dish. No sponges.

Keep a cuttlebone in the tank.
Substrate: primarily a deep layer of damp eco earth, and some play sand on one side. could go sand on half and eco earth on the other half but my crab loves the eco earth. I use 3 bricks of it and change it out twice a year on average.
Get a humidity gauge thing and keep it in the tank, crabs need humidity to breathe, keep it over 70%. mine is usually 85-90%
To help keep humidity in, I have plastic wrap over the top screen of the tank lid, not fully covering it but almost, like 1" uncovered.

Food: jurassiDiet , shredded coconut (cheaper at grocery store than pet store), grapes that I break open, sometimes shrimp, sometimes peanut butter. sometimes raspberries.
Change out food daily.
If crab buries itself to molt leave it alone. If crab does a surface molt (only happened once) keep the other crabs away.
"Bathing" crabs is bs, doing that I believe is what killed one of my crabs early on (I started out with 4).

Shells, turbo shells are what my crab likes but this can vary I guess it's crab preference. I keep 2 extra shells in the tank, after trial & error I was able to get the right sizes I needed from naplesseashellcompany .com

I keep 2 small heating pads stuck to the outside of the tank on one corner- one on the bottom and one on the side down low.

That's the basic overall care summary do I feel bad that this crab is living a solitary life with no friends for the past 19ish years? yes I do. However, at this point any smaller crab I would put in there would immediately be devoured. And if I somehow found another crab the size of this one, it would be a bloody fight to the death. Therefore, this guy remains a solo buddy but he seems to be happy. If you have any questions hit me up on tiktok @ThatBarry
I don't normally look on this site, was just here to research bc crab came up from its annual molt & had old molt stuck to a leg. But, he went back down for a couple days and came back up & had resolved the issue on it's own. I just happened to still have the tab open and saw your post at the top