the critters are creeping

[sterling007]

Well I guess the inhabitants of my new live rock have decided to check out the neighborhood
Today I "did in" a mantis shrimp and now I'm trying to figure out what this thing that is SLOWLY coming out of it's hole is. Looks like a little tarantula, but I'm pretty sure it's a crab of some sort. After discovering the mantis it's kind of scary. What else should I worry about.

 

[sterling007]

Yup, it's some sort of little crab. Kind of ugly, and hungry. it's about 3/4 inch and blends into the rock real well. Any ideas.

 

[glazer]

Wow sterling!... how odd/funny. I got a little "tarantula" as well on some recent new rock. I was just sitting here trying to get a better look at him. I think the little b@st@rd is eating my coraline! I don't know much about crabs as I have never kept any other than hermits and this ain't no hermit. Hoping someone else gets on her and lets us/me know what it is.
I know what hole he frequents and got no probs with nukin' is sorry litte spider lookin' butt!...lol

 

[sterling007]

Hey Glazer, the little tarantula-looking one is NOTHING compared to the monster that's crawling out of another rock!!! Oh My G*d, what is this thing!!! Will someone please help. Are there such things as big hermit crabs without the shells?? This thing looks like a big black bubble coming out backwards with legs!!! It shoots right back in if I move. I only have lights on one end of the tank. I need to find a flashlight!! HELP

 

[blondenaso1]

whach out it might be a giant man eating red sponge LOL

 

[sterling007]

Thanks alot, wise guy
Actually it IS some sort of crab. It's about 1 1/2 to 2 inches, with a huge claw. So can anyone actually help me please. Do I want this? It looks like it could inflict some damage. I'm only guessing on it's size from what has been in view.

 

[wisconsin reef]

sound like you got a fidler crab i would not worry if you dont have coral its ok with fish good luck and they dont bite much

 

[nm reef]

Really hard from the info provided to even make a guess...but there a re a few sites that have info on hitch hikers in general.....
<a href="http://www.reefs.org/hhfaq/pages/main_pages/faq_rock3.htm" target="_blank">hitch hiker FAQ</a>
This one has helped in the past.

 

[njdiver]

Not an expert, but one of the things I was advised to do was dip the live rock in a higher salinity water for about 5 minutes prior to adding to the tank, supposedly it would chase the little critters out. Anyone know for sure if this works???

 

[tjkohler]

One way I've heard of getting rid of crabs is to lean a tall glass (drinking glass) next to their home and put something for them to eat in the glass. Once they go in to get the food, they can't get back out because they can't climb the glass. This way you can at least banish them to the sump while you wait to find an ID.

 

[bluemarlin]

I've heard of people doing a misting of LR before putting it into their tank. Its a curing process during which the rock is sprayed or misted with saltwater. I guess the crabs and other unwanted critters leave the rock and can be captured that way. I've heard of another way to cure rock by keeping it in a bucket of saltwater and keep a heater and a powerhead in the bucket. I guess the theory here is that you watch the rock and the bucket for anything coming out.
Personally, I hate buying new LR and I avoid it at all costs. Its great when some nice wanted creatures come in but when they are unwanted its really a pain!

 

[dsa_mom]

We had two unwanted crab hitchikers on some LR, was unable to find a resource with a pic that matched--took one crab in to the LFS for ID and they called it a common rock crab--it had hairy legs and a sort of terra cotta colored body. The second one was allowed to stay until I saw it eating coralline and making lunges at the fish. I saw it on a particularly easy to remove piece of LR and just reached in and picked up that piece, put it in a small container of salt water, took it to the utility room and put the LR in the sink, gave it a rinse of tap water and out comes the crab. The LR went back into the tank within a few short minutes. The crab never made it back.