scary giant crab - how to safely remove

[malkore]

I'm guilty of not removing all critters from live rock that weren't known to be safe. I left a small crab in the tank when I put the live rock in. Then a week later I realized I shouldn't have...but too late.

Well now its 3 months later...and last night i see the crab dart for a piece of food. This thing's probably 2" diameter body, and has so many hairs on it it could pass for an aquatic tarantula.
I have yet to lose a fish, mushroom or yellow polyp...so this crab doesn't appear to be a danger.
However I'm still afraid he's a ticking time bomb, so I want him out. I'll give him to an LFS in case they can sell it.

will a pair of rubber kitchen gloves keep my hands safe from the crab and any defensive mechanisms he might try to use?

 

[austinsdad]

Mine is about an inch across. Grayish looking and very hairy too. His claws are dark brown. Wondering if we've got the same thing. Mine never puts himself in a position for me to grab him with my hand, so I'm interested in any suggestions others may offer too. Can't get a good pic, so maybe someone recognizes the description and can tell me what it is. My LFS says it's a coral crab from my description. Says it'll get big - 6 inches or so and wreak havoc someday. Now, that's scary!

 

[ellisz]

When mine got big they were out in the open more so it was easy to catch them. I used an old algae scraper to place him in a cup and he is now in my 29 gal

 

[itzafugasi]

well, i had 2 im my tank that came w/ my live rock. im pretty sure its the same crab, hairy, blends in very well w/ the rock cuz he has coralline algae on him (or what looks like coralline). anyway, i had a firefish for about 2 weeks - beautiful fish btw - and as you may know they hide in the holes of the lr. so, this damn crab about the size of a quarter, went into the hole, and killed my firefish. i was sooo ticked off. luckily i got that crab but i have another. so i refuse to get another fish until i catch that damn crab!!

 

[malkore]

Yeah, my wife told me "do not use my kitchen tongs!"

Yep, sounds like the same crab...covered in coralline so you can't hardly see it unless it moves. I'm going to have to pull a lot of live rock to get to him too, which just adds to the annoyance factor. I do think he killed the mantis I had...I haven't heard any clicking in over a month.

Kids...do NOT leave crabs in your live rock!

 

[quarryshark]

You can try leaning a glass up against your rock and tied down a piece of meat with a rubber band at the bottom. If he goes to get the meat, he will not be able to climb out.
Paitents is the key. it took me 2 weeks to catch my mantis.
I am also trying to catch a suspect crab right now.
Good luck all!!!
Or if you see him in the open, some say you can spear them. (I don't have the heart to do that though).

 

[steve r]

in another thread i have going i lost a new blenny ( our first fish ). we added him because it looked like we were cycled and our cleaning crew was doing really good after a week. when i found the blenny he had his eyes chewed out and a chunk out of his back. i didnt see any hermits near him. i know i left a few crabs in the rock and i think i have a mantis. i hear clicking alot. is it possible that a crab or mantis killed our blenny. he was a pretty small bi color blenny about 1.5" and was hanging out in several holes in the live rock.

any thoughts?
steve r

 

[austinsdad]

Steve, just 'cause the hermits weren't near him when you looked doesn't mean they didn't just find a dead fish and started a buffet line. Hard to say what killed him. The crabs, mantis, or other illness could've killed him.

Kurt, I'll have to try that glass. You talking about a drinking glass? Maybe a tall shot glass would work since I'm sure the trap would have to set in areas where there's a bunch of rock? This fellow doesn't seem to wander too far away from the rock.

What kind of meat? Shrimp?

 

[Clown Monarch]

This thing's probably 2" diameter body, and has so many hairs on it it could pass for an aquatic tarantula.

Ugh. A harpoon might work, or a shotgun as a last resort.

 

[steve r]

i figured. just seeing if it was even a possibility that something killed him other than the water. but i think i am just grasping at straws

steve r

 

[quarryshark]

Kurt, I'll have to try that glass. You talking about a drinking glass? Maybe a tall shot glass would work since I'm sure the trap would have to set in areas where there's a bunch of rock? This fellow doesn't seem to wander too far away from the rock.
What kind of meat? Shrimp?

Ya, a fairly tall glass, or you can cut the top off a 16 OZ plastic bottle, but you would have to weight that down, much lighter than the glass.
I caught my mantis be using scallop shavings, however I'm sure small pieces of shrimp would work fine.
Plan on catching a few of your other critter. I caught at least 5 hermits and one of my cleaner shrimp before I got him.

 

[malkore]

Oh, and I'll definitely take a photo when I get him out tonight. Cuz when he went into the tank, he was maybe 1" across, counting his legs.

 

[Cafe Jeff]

A word to the wise, be careful of who you tell you have crabs.
Doing so could seriously impact your social life. Jeff

Seriously. Good luck with the crab hunt. I'd love to see a pic of the b*stard.

 

[Kohan Bros.]

the crab most likely in your tank is a decorator crab some crabs are hard to cath but i suggest you try looking at night with a flashlight since most are nocturnal and place a small amount of food in a net then wait for him to go inside

 

[RocketSeason]

I was able to remove a couple of larger crabs using my net.

The larger ones seem to be more bold and so therefore they move out onto the sand away from the rocks. Its easier to get a net on them when they do that.

 

[ChrisB]

im not trying to change the subject but all this talk about agrresive crabs have got me thinking my pompom crab might be dangerous. i dont think this crab is but just to be safe

 

[malkore]

I had to pull rock to get to him, and it was rough...but I did it.
My camera's not very good, and I didn't have anything handy to show the scale/size of this thing...but the tub he's in is an 18 gallon rubbermaid tub.

 

[luckycat]

I used an XTerminator mantis shrimp trap, and successfully captured about 7 crabs in my tank that I was never able to get with the "tilted glass with food" trick. Got my largest crabs in that mantis shrimp trap, I was pleasantly surprised.