CRAB and FISH
- Thread starter salth20newbie
- Start date
AaronM
New member
How big are they? I reckon it'd be o.k. I have a few big hermies, damn lost my tape measure, only know cms, like 2 or 3cms. Although they seem big, really their pincers are pretty small and ineffectual. My clown fish tell my hermies off by flapping against them, and sometimes my lawnmower blennies just fats out and lays on a hermit. They're not aggressive...
MarineBioMel
New member
LOL, they look like they are posing there. Very cute hermies! They look pretty friendly to me!
AquariumBiology
New member
I'd worry alot more about them bothering coral than fish... that type can get pretty big. They can trample bulldoze corals, but they wont eat fish that aren't already near death.
BEASTIEPENDENT
Member
Hi newbie 
Hermit crabs are normally no danger for any fish. They don't bother living beings, but they do like carrion in addition to their algae scraping.
Clibanarius signatus gets quite big for hermits though. It is listed with 6 cm Carapax length. And yes, they are a little bit like a Bull in a china shop.
Hermit crabs are normally no danger for any fish. They don't bother living beings, but they do like carrion in addition to their algae scraping.
Clibanarius signatus gets quite big for hermits though. It is listed with 6 cm Carapax length. And yes, they are a little bit like a Bull in a china shop.
donya
New member
hermits in the OP appear to be C. vittatus to me (a common gulf species in the US) rather than C. signatus. If you think I've IDed wrong, I would like to know what features distinguished them as signatus to you since I have seen little good photo documentation of signatus.
I wouldn't put C. vittatus in with any fish small enough that a stray nip could be a serious injury or small enough that they could be cornered into a hole in the rock. Although the species isn't the most aggressive large hermit, they are not one I'd call peaceful except with their own species. Reasonably sized fish with no injuries or other health issues will probably be safe.
BEASTIEPENDENT
Member
Hi donya,
I was able to find two pictures with scientific background – and You seem to be right. These species are quite hard to differentiate but C. vittatus seems to have pale blue eyes – as seen here: http://www.ucs.louisiana.edu/~rtb6933/shrimp/students.html (image at about the middle of the site) - whereas C. signatus has black and white eyes – as seen here: http://www.mnf.uni-greifswald.de/in...logie/mitarb/diplomarbeit-corinna-krempl.html (here the image is even larger: http://www.mnf.uni-greifswald.de/fileadmin/Cytologie/Clibanarius_signatus_longitarsus2.jpg ). In the upper picture it does look indeed as if the two hermits had pale blue eyes.
There is a third species looking very similar, C. striolatus, but this one has no striped eye stalks like the other two.
Thanks for Your hint, learned something myself!
I was able to find two pictures with scientific background – and You seem to be right. These species are quite hard to differentiate but C. vittatus seems to have pale blue eyes – as seen here: http://www.ucs.louisiana.edu/~rtb6933/shrimp/students.html (image at about the middle of the site) - whereas C. signatus has black and white eyes – as seen here: http://www.mnf.uni-greifswald.de/in...logie/mitarb/diplomarbeit-corinna-krempl.html (here the image is even larger: http://www.mnf.uni-greifswald.de/fileadmin/Cytologie/Clibanarius_signatus_longitarsus2.jpg ). In the upper picture it does look indeed as if the two hermits had pale blue eyes.
There is a third species looking very similar, C. striolatus, but this one has no striped eye stalks like the other two.
Thanks for Your hint, learned something myself!
BEASTIEPENDENT
Member
You're welcome. I saved this myself for comparisons in the future – C. signatus, striolatus and vittatus really look too much alike.
I saved this myself for comparisons in the future – C. signatus, striolatus and vittatus really look too much alike. 
Gill_bucket
New member
Those little guys wont hurt fish IMO Your next question should be which fish. With a 20L there are going to be lots of beautiful fish at your LFS that just wont work because they will get to big. But have no fear there are also tons of beautiful fish you could keep in a 20L. Just make sure you are well informed BEFORE you go shopping ;-)
salth20newbie
New member
Thanks you guys!!! No fish yet....my nitrate levels are not good 
and havent been for a while; 10 weeks into my tank and still cant figure out whats going on! Crabs are doing great, eating, walking, discovering the tank, etc. I have other life- bristle worms, copepods in there so im not sure whats going on any ideas on how to fix nitrites and nitrates?
and havent been for a while; 10 weeks into my tank and still cant figure out whats going on! Crabs are doing great, eating, walking, discovering the tank, etc. I have other life- bristle worms, copepods in there so im not sure whats going on any ideas on how to fix nitrites and nitrates?
donya
New member
What levels are you getting, and how often are you doing water changes? Your hermits are a hardy species, but you should still try to minimize exposure to nitrites and high nitrates. Bristleworms are far hardier so they can't be used to gauge whether the environment is ok or not. You should decrease feeding frequency and probably do some extra water changes until the excess nutrient problem is resolved.
