Your crab may be molting if it is out of its shell and not moving. Signs of molting include general lethargy, less antennae activity, tangled and confused-looking antennae, an ashy exoskeleton, and dull eyes (like human cataracts). Your crab may remain still for long periods of time, and it may even bury itself in the sand as a safety tactic.  Smaller, quickly-growing crabs can molt every few months, while larger crabs tend to molt about once a year. Note the dates and duration every time that your crab molts; this way, you'll know what to expect. If your crab is new, or if you haven't seen it molt before, you'll need to wait it out until you're certain.  Wait several days. If there is no fishy smell, there's a good chance that your crab is molting. Molting usually lasts about two weeks, so you may need to wait some time before you are absolutely sure. Consider whether your crab has been eating a lot over the past few days. Before a molt, a crab will store extra fat and water in a small blackish "bubble" – usually on the left-hand side of the abdomen, just under the fifth pair of legs. However, do not assume that a crab is molting just because he has made a bubble. Molting crabs are vulnerable to stress and injury from other hermit crabs due to their inactivity and their soft new exoskeleton. If one of your crabs is molting, and you have other crabs in the same tank, put the molter into a temporary "isolation tank" so that it can shed in safety and privacy. It is very important that hermit crabs are not disturbed during the molting process. If you only have one tank, improvise an "isolation cell" within that tank. Cut off the ends of a 2-liter soda bottle, then sink the edges into the sand to protect the molting crab. Be sure that the top of the "isolation cell" is open so that oxygen from the surface can replenish the space.
حدد ما إذا كان السرطان يطرح هيكله. ابحث عن "فقاعة سميكة". اعزل السرطان المنسلخ عن السرطانات الأخرى.