Hi there!
Glad you stopped by the HCA, This is definitely the right place to ask questions.
The first thing I want to direct you too, is the basic care guide. I think you will find a lot of useful information in this thread that can really help!
http://www.hermitcrabassociation.com/ph ... 51&t=92457
I will touch on a few things, but like I said almost everything can be found in the careguide.
You are going to want to add some additional substrate to your crabitat. The basic minimum suggested is 6inch. A lot of people, myself included, use a mix of play sand and eco earth (coconut hide), 5:1 ratio. So if you can get a bag of playsand from lowe's or Home Depot and add that in, you should be at the right height. Its also a lot cheaper than using just eco earth! Also, you do not need to clean out your tank each month. The only time you really would need to do that is if you had a bacterial bloom.
Gauges are also very important as the temp and humidity level are crucial to our crabbies surviving! Both temp and humidity should be at 80 degrees and 80%, they can be higher too, but this is just a rule of thumb for most crabbers the best thing to purchase is a hygrometer to make sure temp and humidity levels are maintaining. So if you are able to get that up, with another lamp or a heat pad, that would really, really help out your crab. And could actually be the reason you are seeing him acting so different. I would recommend retilebasics.com for a UTH. They are cheap, can be insulated and work really well!
Did you say you didn't have a lid yet? First and foremost, you will need to get a lid on your tank! Without a lid, you have no way to contain heat or humidity. Your crab really needs both of these or could die. The humidity is crucial for them to breath as they do have gills. Remember, these guys are from tropical places where it rarely dips below 80 degrees, except at night. So lets get that lid! Until you do, I would saran wrap the top.
Pools or water are also very, very important. Crabs need both salt and fresh water to bath, drink and hang out in. They carry water in their shell to replenish their gills, so they need to be able to fully submerge in both fresh and salt water as they need too. I would not continue to give your crab baths. Once you have the proper pools set up, they will go in when they choose/need too. The only time you should bathe a crab is mites, before adding a new crab to a tank and after a molt before adding them back in to the colony. You can toss your sponge from the water dish. They really don't have a purpose other than carrying bacteria. If you do keep it, it will need to be boiled every couple of days so it does not contaminate the water. You can give them sponge to munch on as a treat, but I wouldn't suggest putting it in the water!
As mool mentioned, definitely add protein and calcium to your crabs diet. This could have been the reason he was attacking & killing other crabs as well. Most don't use the pellets either, so check the list to see if they are OK to give your crabs. IMO I would just toss them and feed them the fruits, veggies, proteins and supplements that you have at home! Here is a link to the safe food list;
http://www.hermitcrabassociation.com/ph ... 25&t=92557
So back to your question, its possible your crab is just staying still to gain back energy from his recent molt? BTW, was it a surface molt or was he under the 2inch of sub? Or else, he could be on the verge of passing away. Heat, humidity, proper food and water & sub depth are really crucial for these guys to survive. He might not be able to hold on anymore, after all, he is already weak from the molt. Its possible if you can quickly change the things mentioned he could pop back to his old self, but usually when the damage is done internally, there is not much you can do.
![Sad :(](./images/smilies/icon_sad.gif)
Hopefully he will be a little miracle crab and perk back up once you can get things adjusted. Good luck and keep us posted! I am sure I missed some things, so hopefully others can chime in!
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