HCA: Hermit Crab Association

We have a very pushy and restless crab.
our set up:
10 gallon glass tank/glass lid
78 degrees/78-82 humidity
side heater - moss pit
5 inches play sand
cholla to marsh pit
salt water pool/fresh water pool
food from Crab patch/fresh fruits
working on second floor shell shop

2 crabs - 1 small 1 medium

OK, so we got our crabitat set up and went to Petco 2 days ago and got two crabs. I think PP's.
In the box on the way home, medium guy Edie kept pushing little Marshmellow around. Got home and there was a brief fealer fight and marshmellow headed straight for the cholla and marsh pit. Hung out there all day.

Edie went round and round the glass sides looking for a way out. This continued for a long time and I felt bad because we only have the 10 gallon. But eventually he went up to the marsh pit and settled in. First night he switched shells.
Both hung out in the marsh pit, little marshmallow on top of the moss and Edie buried. Next night Marshmellow came down and was eating. Edie came down and pushed her out of the food and went round and round and round only stopping to shove and roll little Marshmellow. Finally she ran when he would come toward her. She headed up to the pit but managed to change her painted shell at some point in the night.

Today, Edie managed to climb some fake plant and was hanging on the small slit in the lid. I got him down and he is going round and round the glass again. Then he managed to once more climb the fake plant and is hanging on the small slit in the lid.

I really feel awful. Edie seems very unsettled. I think our tank is way too small for him and I hate that Marshmellow seems to want to stay away from him. We got the crabs because we fell in love with little Marshmellow three weeks ago at Petco. We were thrilled when we had our set up and went back and she was still there.

It has crossed my mind more than once to take Edie back but I hate to do that. We originally planned on getting three small. Edie looked smaller in the Petco but when he changed shells we realized he was bigger than we thought. He fits into the medium shells I ordered from Crab Patch.

Any suggestions on what to do? We are looking to get a 20 gallon but I don't think even that would help little Marshmellow. Would posting on craigslist for someone who has experience and a large tank be appropriate? I don't think I can return him to Petco but we aren't feeling like a happy family.

P.S. We live in the Richmond, Virginia area.

Dont worry this is actually completely normal!

What Edie is doing when running around the sides of the glass and trying to find a way out is normal. Hermit crabs are little escape artists. (And once one figures away out, they all follow his lead )

What Edie is most likely doing is showing dominance over marshmallow. If he is not rolling her back and forth and mounting on top of her shell, I don't think it is a problem. What you can do is try to bathe both of them in dechlorinated fresh water so they feel neutral towards eachother. This happens in a lot of people's tank so don't worry too much.

Thanks for the reply.

I am definitely a worrier. I spent time working on the tank and didn't read anything on crab behavior. Seeing Edie go round and round made me feel so bad as they weren't really moving at all at Petco. It just hit me that he once had a large enviroment and now he only has 10 gallons filled with stuff.

I am going to redo the decorations in the tank and see if I can make more space. I found smaller bowls that should still allow them to emerse. I used crocket mesh and aquarium silicone for the original glass bowls. Can boiled sea glass be used safely to line the new bowls? I took down the vines so there shouldn't be any more climbing to the top and hanging on to small slit in the glass lid. I am also making a new hidey hut as the one I have doesn't have a large enough opening for Edie and Marshmellow hasn't gone into it at all. The shell shop I originally improvised just ended up leaning so I am working on something new there too. Hubby says I should chill and we can get a 20 gallon in a few months.

I will just watch and hope that Edie doesn't get too aggressive with Marshie. He did lift her and move her and make her roll a few time.

This morning Marshmellow is nowhere to be seen. There is definitely sand moved so she may be underground. Edie is buried in the moss pit. No limbs or anything obvious amiss.

Even when they get over being in a tank, hermit crabs are used to roaming for miles and miles in the wild. Doing "laps" in the tank is one way for them to get some excercise. Sometimes some crabs are antsier than others, and need more space. If he feels like he's too cramped with the other crab, he may pick fights with him more often than usual. But as mentioned, poking or punching or even charging at other crabs is normal, as long as it doesn't turn into a shell fight (where the attacker is actively trying to get the other crab out of his shell) then it's fine, and he's just showing him who's who in the tank.

I was just going to say the same thing! Even in my 135 gallon, they still walk laps at night around the perimeter of the tank. 11 feet round trip, and they'll do it for hours. It is partly because they're not used to a tiny environment, but it's also because they're hardwired to explore and escape so they'll always be testing for ways out. (Kind of like cows.) If you ever get the chance to upgrade they'll definitely appreciate the space, but what they're doing now is not abnormal. They should calm down after they've molted!

Can he safely be on the lid without getting out? If so, I'd just let him be up there. I actually set up my tank so that the crabs can get to the wire lid. Several of them enjoy climbing up there and it's good exercise. Just don't walk up to the tank quickly when they are on the lid. Their automatic reaction of pulling into their shells results in a big plop onto the tank floor when that happens.

I would think so, I mean one of my crabs gets up and down from climbing the wire lid So I see no trouble in it.