Crab Trap

[NeuroDoc]

Hey everyone,

I finally have a 24g aquapod up and running. After all the research I did (probably not enough) I failed to realize that when buying my rock that I would need to deal with hitchhiking crabs. So now I have 2 or 3 crabs in my tank and I want them gone. I have read about the glass, nylon, and soda bottle methods of trapping them. I am going to try the soda bottle trap.

What is the best bait to use? Will it lure a crab down from a top rock to the bottom of the tank, or do I need to place it close to where I think the crab is?

If this doesn't work, I am willing to pull the rock out, but then don't know how to get the damn things out of the rock without killing everything on the rock. Are there any recommendations?

Thanks in advance.

 

[NaH2O]

The crab I tried to capture would come to about any food source, but it never did go into the glass (I ended up pulling out the rock). Give the bottle trap a shot, the crab should come to the food source, and if you have room in the tank, leaving it close to the crab's home will probably be a benefit. Do you have something like a piece of shrimp to bait with? Let us know how it goes...

 

[NeuroDoc]

I was thinking I would buy a couple of shrimp or scallops to use as bait. Is there anything better?

 

[DonW]

I was thinking I would buy a couple of shrimp or scallops to use as bait. Is there anything better?

Interceptor. Sorry couldnt resist.


Don

 

[NaH2O]

NeuroDoc - that should work fine. Let us know how it goes!

 

[NeuroDoc]

So I built a trap from a plastic bottle (2L was too big so I used a 120mL water bottle). Didn't make it to the store last night to buy shrimp or scallops so I dumped in a cube of frozen mysis shrimp. They sat in the bottle and didn't float out. Didn't catch anything though. Hopefully trying with fresh seafood will be more successful.

Also, what do these stupid hitchhikers eat? I ask that because my wife fished a dead one out of the tank this morning. I was hoping (probably unrealisticly) that they might all die, as my tank has only two fish (ocellaris clowns), 6 margarita snails, and 3 blue-legged hermit crabs, and so there is not much detritus for the rock crabs to eat. Now if they eat algae, that's another story, I got plenty of that.

 

[bwester04]

I'll send you my picasso trigger, he'll terminate them, then you can send him back to me:lol: jk, Are they stone crabs? I live on the gulf in texas and pick them from the rocks on occasion to feed my triggers and puffers, those suckers have some massive celipeds for a little crab.. Hope you get them out!
This is my first post btw, and I have to say, this forum is very friendly and knowledgable, compared to others I have been on!

 

[NaH2O]

bwester04 - Welcome to Reef Frontiers!!!

NeuroDoc - was the hitchhiker your wife pulled out a molt, or was it the actual crab? Alot of times the molt looks like the animal, but upon closer look there isn't any "meat" to it...if that makes sense. Keep your eye out at night with a red lens. How many hitchhiking crabs do you think you have?

 

[NeuroDoc]

bwester04 - Welcome to RF. I too have found everyone here to be friendly, polite, and helpful. Thanks for your reply.

I believe they are stone crabs. They are fairly small, gray, have hairy legs and large pinchers. They hang out in the rock, constantly just sweeping their pinchers out of the hole and back in.

Nikki-I will look closely when I get home tonight. I hope that it was a real dead crab and not just the molt. We'll see. My wife thought she was so brave going after this thing.

So what do these things eat? Also, I am hoping to get a much larger tank in the near future. How do I get rid of these things when I get new rock and before I start stocking my tank? I have heard of pouring soda water on the rock to get rid of them, but won't that kill of a lot of the beneficial stuff I want to save?

 

[NeuroDoc]

Well, it was a molt. Damn! Bought some prawns tonight, and will try that out in the trap. I'll keep you posted.

 

[Fragman]

I have used this method with success. I used clam meat and a small mayonaise jar. I think that the wide mouth on the container is a factor. I placed the jar at a 45 degree angle up against the live rock near were he hangs out. I tried all sorts of other things for weeks. This method got him on the first night.

Good luck!

Paul

 

[NeuroDoc]

Thanks for the words of encouragement. Two nights of using the water bottle and nothing. I have pulled four molts out of my tank. I will try the open bottle next. If that doesn't work I am very tempted to tear the tank apart and try to wash out the rock with a hose. How dangerous is that?

 

[bwester04]

Sorry to hear you havent been able to catch them. I say if you dont mind, I'd go for taking out the rocks to find the crabs.. Sometimes I feed the fish in my tank juvenile blue crabs that I net around here and some of the lucky ones scurry into the rockwork, they are menaces and I have to dig through the rocks to get them! Good luck to you!