Hermit Crabs getting killed

[MaxxGlock]

I am having a problem with my scarlet hermit crabs dying or getting killed. Every morning when i wake up there is a dead hermit crab, or pieces of him laying in the tank. Most of the time they are whole, with just the eyes and tail missing. Is something killing them? There are a couple of empty shells in the tank for them. I have a 55 gallon tank with the following inhabitants.
20 turbo snails
25 scarlet hermit crabs(or at least there were)
25 blue legged hermit crabs
5 peppermint shrimp
3 emerald crabs
1 sally lightfoot crab
1 coral banded shrimp
1 tuxedo urchin
3 brittle stars
1 sea cucumber
1 royal gramma
1 firefish goby
1 pygmy cherub angel
1 sixline wrasse
1 yellow headed goby
1 yellow headed jawfish
Bubble Coral, Torch coral, various mushrooms, various polyps, anemones, leather coral
I dont think its a mantis shrimp because the only thing showing up dead is the scarlet hermits. Does anyone have an idea what is going on? Could it be 1 territorial crab that is pissed off at everyone else? I just added 2 live rocks from the LFS 1 week ago and it was after this addition that the hermits started croaking. It was very nice live rock, lots of stuff on it, that is how I got my tuxedo urchin, he must have been in a hole. Everything else is very healthy.

 

[Anonymous]

I had a small tank a while back and it had 6 Scarlet Reef Hermit crabs. After about a month, I started seeing them die one by one. Except that, eventually, more died than I had in the tank, and yet I still saw a few now and then on the rocks.

You probably have too many in your tank to count, but I found out that several of the carcasses were actually the crabs just moulting and growing, and that they weren't dieing at all. Before I sold my tank, I believe on final count there were 4 left out of 6 and yet I had seen at least 8 crab remains in the tank, so they obviously weren't all dieing.

This may not be what is happening in your tank, but I thought I should mention it.

 

[Anonymous]

Too bad it's not the blue leggs dieing. It would save you from having to take them out when you notice that they have all changed clothes. I just got the last three out of my tank over the weekend. All three were wearing snail shells from the new nassarius, margarita, and cerith that I just put in the tank a couple of weeks ago. So I kick em outa da house for good. Bastards!

[ March 04, 2002: Message edited by: Louey ]</p>

 

[backerma]

I've witnessed the same with mine and have found it is a skin molting process. As they grow they molt their skin and will eventually look for a larger shell to call home. I had one that would molt about once a month and even switch shells a couple of times a day. I guess he wanted a different look or maybe she could decide what to where.

 

[LiveRockr]

I have found that any crustaceans you get will almost always molt within a few days of entering a new tank. I first noticed it with cleaner shrimp, but Hermit crabs leave behind a startling likeness of themselves when they molt. The only thing about a molt skin is it doesn't stink like a dead hermit crab would. My guess is that you are not missing as many as you think. Do you HAVE a mantis shrimp. You'd know it if you had, because you'd hear a persistent popping sound after lights out...usually two or three in a row. It's how they crush things, or slice things, or scare things away. But if you don't hear that, they have probably just molted, cause it's pretty hard to kill a hermit crab, they would probably be the LAST creature in your tank alive after EVERYTHING else dies.

 

[MaxxGlock]

I would accept the molting theory except, when your crabs molted did they leave flesh inside the molt? I have seen shrimp moltings and these look nothing like that. You can see flesh coming out of the crabs as if something was chewing on it. If molting were in fact the cause, wouldnt I also see the blue legs molts? I am fairly new to saltwater animals so I really don't know a whole lot about them. I remove the dead hermit crabs from the tank as soon as I see them and I can assure you that they are not just molts. Any other ideas?

 

[esmithiii]

When mine molt it looks a lot like they simply keeled over.

Ernie