More fun with crabs!

[Karthalin]

I have one particular rock that is teaming with crabs (saw 4 at one time). They are all small (for now) but I figured I would post a few pictures and a video of the biggest one. My concern at the moment is that they will ruin the rock they are on. The nice thing about them though is that they are keeping a large leafy macro algae contained. The rock was covered with this green plant but now its down to a few leaves. Below is a link to another crab identification thread and I am pretty sure the pics/video below are going to be the same kind, but I am certainly no expert.

http://www.reefcentral.com/forums/showthread.php?t=2049932

So, reefcentral.com, what should I do about this little guy?


Skip to 27 seconds, the camera finally focuses enough to see him. Sorry for the sideways view, I forgot to fix it before I uploaded the vid.
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http://img8.imageshack.us/img8/353/20110804205712.jpg

http://img823.imageshack.us/img823/8016/20110804205547.jpg

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[thebkramer]

get them out.. black sharp claws = bad news!!!!!

round claws are usually the good guys but IMO no crab is a good crab in a tank lol

[vwwanksta69]

I would suggest getting rid of them as soon as you can

[Catastrophi]

Get them out ASAP. I had a hitchhiker that was killing my SPS.

[Karthalin]

Problem is nabbing these little buggers. They are too fast to tweeze out and that rock is full of holes. I have been leaving a smooth glass in the tank with meat at the bottom and I caught three crabs previously, but nothing the past few days. I need a crab eating fish/octopus in there for a night or two... :D

[brian762]

Dip the rock in fresh RO water for a bit.

[Lynnmw1208]

I agree, get them out :thumbsup:

[thebkramer]

Dip the rock in fresh RO water for a bit.

+1

use separate bucket.. throw rock in with RO water.. they will try to high tail out of there :lol:

[raylost]

Or you can try this!

See this link
http://www.reefcentral.com/forums/showthread.php?t=2050712
http://i965.photobucket.com/albums/ae133/raylost/photo-1.jpg

[Dazed1]

Or you can try this!

See this link
http://www.reefcentral.com/forums/showthread.php?t=2050712
http://i965.photobucket.com/albums/ae133/raylost/photo-1.jpg


I tried that to catch my peppermint (after reading your thread). Caught my clown fish (guy just wants to eat!) and my skunk cleaner. But no peppermint :(

[raylost]

I tried that to catch my peppermint (after reading your thread). Caught my clown fish (guy just wants to eat!) and my skunk cleaner. But no peppermint :(

I got all five pepermint out in two days I use small plastic soda bottels I put some fish eggs an it work.

[billdogg]

If you have a sump or better yet, refugium, just put the rock in there and let them live. If they are someplace they can't hurt anything, they are just another part of your clean up crew.

[WetShepherd]

+1

use separate bucket.. throw rock in with RO water.. they will try to high tail out of there :lol:

Just a couple of questions.

First, by separate bucket do you mean dunk the rock in bucket 1 with RO water, then place the rock in bucket 2 to retrieve the monsters? If so, what is in bucket 2 (nothing or tank water)? How long did you dip when you did it successfully?

Second, will this kill off a lot of the good stuff in the rock?

I'm asking because I've trapped all I can trap and am considering this method for all of my rocks in a newly cycling tank. I have several small crabs (some ID'd in another thread here) including at least one gorilla. These remaining guys are extremely stubborn.

[thebkramer]

Just a couple of questions.

First, by separate bucket do you mean dunk the rock in bucket 1 with RO water, then place the rock in bucket 2 to retrieve the monsters? If so, what is in bucket 2 (nothing or tank water)? How long did you dip when you did it successfully?

Second, will this kill off a lot of the good stuff in the rock?

I'm asking because I've trapped all I can trap and am considering this method for all of my rocks in a newly cycling tank. I have several small crabs (some ID'd in another thread here) including at least one gorilla. These remaining guys are extremely stubborn.

I meant just use one bucket with RO and put the rock in that. yes.. you may have some die off.. but it will be worth it!! compared to crabs eating/killing corals, inverts and sometimes even fish!!!
If you are concerned about die off & don't want to chance it.. you can also use a bucket with SW and put rock in there. Keep it dark and check the bottom here & there for the crabs.. this can take some serious time though. you can also entice them by putting a piece of shrimp (table shrimp) at the bottom of the bucket away from the rock.. when you see them munching.. just yank the rock out before they find their way back to it...
Good Luck!!! :bounce3:

Edit: DEF get that Gorilla out of there!! I've had some horrible horror stories in my tank! they are one of the worst IMO!!! It took me forever to get him and wreck havoc in my tank!! I finally ended up using a grilling fork and had to stab him :( sad.. but he had to go!!

[mal7887]

I had a tough time catching come gorilla crabs a while back. The method I found that worked best for me was putting a small rock up front then luring the crab over using a stick with a silverside at the end. Then once the crab is on the small rock (they usually hold close to the rock) jerk it out quick and freeze the bastard! Was able to catch three in one day using this method.

[WetShepherd]

Thanks for the info guys - very helpful. I've been using frozen brine shrimp in a media bag (it doesn't spread all over the tank when it thaws) at the bottom of a clear glass leaning on the suspect rock. I'll give a silverside a try and see if that's more tempting to him. He's currently very small and I don't think he ventures off the rocks yet, unlike his striped ilk - I have nabbed several of those.

I have tried the bottle with inverted top but have had zero luck - hence my theory about him/them staying on the rocks.

If the new bait doesn't work I'll be making the RO dip my weekend project with 60 lbs of rock ;) On the up-side, the tank is still cycling so this will only prolong the cycle - not a big deal. In fact I've been siting at .25 ammonia with 0 nitrate/trite for almost three weeks so I'm thinking it could be a long haul anyway.

[mal7887]

He's currently very small and I don't think he ventures off the rocks yet.



Oh he's partying at night I guarantee that!

[thebkramer]

Oh he's partying at night I guarantee that!


:lmao: :lol: :lolspin:

[mal7887]

But def get it out before you stock your tank. We tried catching these boogers for months after our tank was stocked, what a pain it was!

[WetShepherd]

Oh he's partying at night I guarantee that!

That's what I figured - the only way I even knew he was there was that I spotted him after suddenly flipping the lights on one night while searching for my first monster (big rock crab).

He and at least one other will absolutely go before stocking begins - the die off from the inevitable fresh water dip will cause an unacceptable ammonia spike for a stocked tank so I'll be preserving that option. I have several weeks before stocking is even an option anyway.