Hermit crab, molting or dead?

Luan B.

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Hello everyone,

it’s been a couple weeks now that my hermit crab is “inside his shell”. How long does the molting process last if that’s the case?

1 week ago I picked up to look inside and did move a bit but I’m not sure if is dying or what, also what could be the reason for it? if dies I believe is either a contaminant in the water or he was sick already since I just got him last month, he’s the size of a golf ball, I have other inverts in the tank and they’re all ok.

Thanks
 

Crabs+Shrimps-69

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Hello everyone,

it’s been a couple weeks now that my hermit crab is “inside his shell”. How long does the molting process last if that’s the case?

1 week ago I picked up to look inside and did move a bit but I’m not sure if is dying or what, also what could be the reason for it? if dies I believe is either a contaminant in the water or he was sick already since I just got him last month, he’s the size of a golf ball, I have other inverts in the tank and they’re all ok.

Thanks
Picture please?
 

BonnieB

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Hermit crabs do not molt, they abandon their shells for bigger ones. Make sure you have empty shells for him to move into. Not sure if he’s sick/dying but it could be a protective measure if he’s outgrown his shell.
 

Crabs+Shrimps-69

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Hermit crabs do not molt, they abandon their shells for bigger ones. Make sure you have empty shells for him to move into. Not sure if he’s sick/dying but it could be a protective measure if he’s outgrown his shell.
Really?
I've seen the molts of mine before.
 

BonnieB

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Hermit crabs do not molt, they abandon their shells for bigger ones. Make sure you have empty shells for him to move into. Not sure if he’s sick/dying but it could be a protective measure if he’s outgrown his shell.
Really?
I've seen the molts of mine before.
Yeah, it’s not like a shrimp or emerald crab (and I’m sure others I don’t know of). Hermit crabs have shells and when they get too big they go find a bigger one or kill another hermit crab and take over theirs. I can see where it might look like a molt though.
 

BonnieB

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Hermit crabs do not molt, they abandon their shells for bigger ones. Make sure you have empty shells for him to move into. Not sure if he’s sick/dying but it could be a protective measure if he’s outgrown his shell.
Really?
I've seen the molts of mine before.
Yeah, it’s not like a shrimp or emerald crab (and I’m sure others I don’t know of). Hermit crabs have shells and when they get too big they go find a bigger one or kill another hermit crab and take over theirs. I can see where it might look like a molt though.
Also they shed their ectoskeleton as they grow, perhaps that is what you are referring to as molt. Most is covered by the protective shell and the very front is exposed as the crab emerges to walk and eat. When they outgrow the shell, that’s when they shed the ectoskeleton.
 

Crabs+Shrimps-69

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Also they shed their ectoskeleton as they grow, perhaps that is what you are referring to as molt. Most is covered by the protective shell and the very front is exposed as the crab emerges to walk and eat. When they outgrow the shell, that’s when they shed the ectoskeleton.
Isn't shedding the exoskeleton the same thing as molting?
 

Paul B

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Hermit crabs do not molt,
They actually molt all the time like all crustaceans. I find their shells (not the snail shell they steal) all over my tank and I have a lot of hermit crabs. 😎

Pick it up and smell it. If it stinks, it's dead.
 

BonnieB

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Hermit crabs do not molt,
They actually molt all the time like all crustaceans. I find their shells (not the snail shell they steal) all over my tank and I have a lot of hermit crabs. 😎

Pick it up and smell it. If it stinks, it's dead.
Interesting! I have 3 tanks and tons of hermits and only have ever seen empty shells. I wonder if other scavengers are snatching the ectoskeleton/molt right up. Learn something new every day!
 

Crabs+Shrimps-69

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Interesting! I have 3 tanks and tons of hermits and only have ever seen empty shells. I wonder if other scavengers are snatching the ectoskeleton/molt right up. Learn something new every day!
Crustaceans are supposed to eat their own molts, but for some reason mine never did.
 

BonnieB

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Interesting! I have 3 tanks and tons of hermits and only have ever seen empty shells. I wonder if other scavengers are snatching the ectoskeleton/molt right up. Learn something new every day!
Crustaceans are supposed to eat their own molts, but for some reason mine never did.
Wow! Also something I didn’t know! Thanks for the lessons! I’ll have to complain to my marine biologist/aquarist DIL that’s she’s not teaching me well enough! 😂😂
 

Mr. Mojo Rising

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I've only seen a hermit molt once, they are very small and get blown around by the flow, so its very easy to miss them. They also disintegrate very quickly, within a day. The crab will hide for a day or two, but 3 weeks is very long to not move at all, I might assume its dead. If its dead, then worms and stuff would have eaten it out of its shell.
 
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Luan B.

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I've only seen a hermit molt once, they are very small and get blown around by the flow, so its very easy to miss them. They also disintegrate very quickly, within a day. The crab will hide for a day or two, but 3 weeks is very long to not move at all, I might assume its dead. If its dead, then worms and stuff would have eaten it out of its shell.
Thank you! I picked up to check just in case and was dead :( and it’s been for while I’d say. The question now is: does anyone know what chemical in the water could cause that? I’m getting a ICP test soon but not sure what to look for. Is either that or was sick when I got it.
 

BonnieB

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So sorry you lost him! I have to say IME that sometimes, especially with inverts, you just don’t know, except like what ColorMeGone said if you put something like copper in the system.
 

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