Hermit crab mortality

SaltyDr

New member
I have gotten hermit crabs twice. They all seem to be fine but after a couple of weeks a couple die. It seems like the initial (first couple of weeks) mortality rate is about 20%. My ammonia, nitrite, nitrate, phos are 0. SG 1.025, pH 8.1 (a little low, I'm going to start dripping kalk soon but this shouldn't be a problem) Is this normal? I also lost one of three Mexican turbo snails. The rest of the snails are fine, as is the lawnmower blenny and foxface. No corals yet.
 
Probably starving to death. Do you see them out and about during day light or when you're lights are on?

If so, that's not really normal behavior as their instinct is to eat when it's safe...and that's in the dark!
 
How old is the tank. Also are there a few differant size empty shells for them. They will kill another for there shell. Also could be a preditor like pistol shrimp.
 
The tank is new, put the rock in 6 weeks ago after curing for a week. There are a bunch of empty shells and they seem to be changing shells all of the time. I haven't seen much aggression between them, but occasionally they are next to one another. They are scarlet hermits which are supposedly less aggressive. I guess they might be fighting/killing eachother. Being a new tank there is plenty for them to eat. Just wanted to know if others saw an initial mortality when introducing crabs/snails.
 
my hermits all kill each other. they leave the snails alone, and everything else, but they kill eath other until there is only one left. maybe the same case for you
 
my dwarf blue leg also kill each other off, I have plenty of food in the tank with the 200 lbs of live rock and the deep sand bed and I also have plenty of empty shells for them to swap, every once and awhile you will see just legs laying there and the body will be eaten...
 
I would imagine that as frequently as they molt there is probably a statistically good chance that they are unsuccessful in leaving their old shell and die during molting or are attacked while their shell is still soft by other crabs, shrimp, etc...
 
I've never observed hermit crabs killing each other. I have seen one eating a snail but I'm fairly sure the snail was already dead. I've gotten 3 or 4 orders of hermits and there are usually a few that don't last too long. Maybe it's the stress, they were not healthy to begin with, I'm not sure.

It seems to be the same with snails.
 
It's nice to know that I'm not the only one loosing a few crabs/snails when everything else seems OK/stable. Thanks.
 
Are you sure they are dying and you're not seeing the molt? The first time one of my crabs molted I was sure it was a dead crab as well. It is amazing how formed the ecoskeleton is.
 
Molting is when they shed their exoskeleton because they have outgrown it. Their new "skin" will harden over the following day or two into it's original crabby hardness.

And I thought I had a couple of crabs croak on me but turned out they had just molted.
 
Yeah i was just thinking the same thing baout the molt,it looks just like the crab,it will still be colored up and everything,but its just them shedding,ive never seen mine kill each other.they mess with each other all the time,ive even seen one out of its shell riding around on the shell of another trying to get into its shell.its was preety wild,id never seen one naked,lol.
i was wondering about the pistol shrimp comment,i have one in my tnak with about 30 hermits,ive never seen him attack them is this common? it thought pistols wree reef safe?
thanks
 
I guess it could have been a molt. Didn't think about that. It's hard to keep track of the crabs to know if any are missing. I'll luck in the tank and only see a few, come back later and there are more, others are "missing". They are also changing shells pretty frequently so that makes it even harder to keep track of them. Oh well, I guess it's nothing to get too worried about.
 
They may be starving. I feed mine Nori. After I feed my tangs I drop some pieces of Nori around the tank for my crabs and skunk shrimps to feed.
 
I think there is plenty for them to eat. The tank is only 6 weeks old and I'm still dealing with what was a MASSIVE algae bloom. It has been cut back significantly but there is still more than I want. I had used some LR from the Keys (and Fiji) and the rock had turned totally green and hairy after 2 weeks. I was showing some phosphates and I am guessing it came from the die off from the LR, don't know where else. Running phosguard now. Level is 0 now. It's getting better but still plenty for the snails, hermits, lawnmower blenny and foxface. Won't start feeding until most of its gone.
 
Back
Top