Problem Crab In Tank

[DarrenUnwin]

Hi all,

I recently purchased a new sand shifting starfish but found the animal minus one leg, then two , then half off another. After many nights watching the tank, I found a large (ish) crab of about 1.5 inches accross which I didnt know I had and suspect this is the culpret.

Apart form dismantling the live rock , has anyone had any success in getting problem crabs (steady.. keep if clean) out of your tank. I have looked at commercial traps but they look a bit hit or miss as to whether they would trap it or half the tank instead.

Any advice greatly appreciated.

 

[SkiFletch]

If you know the rock he's hiding in, you can try a magnesium dip. Add say 5 cups per gallon of RO water of either mag chloride or mag sulphate (epsom salts). Warm it up to tank temperature. Remove the rock, dip in magnesium. All crustaceans should exit the rock screaming. I've never tried this myself, but it's the method Anthony Calfo reccomends

 

[sothoth]

If you don't mind taking the rock out, you can also put it in a 5gal (or whatever the appropriate size is) bucket with tank water, and eventually it'll exit the rock and be on the bottom of the bucket. You can just lift the rock out, crab stays behind. I also used a chopstick to help "convince" the crab that he didn't want to stay in his hidey hole forever.

I put him in my 'fuge, but now I realize even that was a mistake, he seems to eat the macroalgae or pick it off the rocks, so that may be the last straw. Don't know what to do with him, he's actually quite beautiful so I don't like the ideal of euthanizing him. Know anyone that wants a free crab?

Good luck getting yours out, it too me a couple of hours of sitting and waiting until mine left the rock on his own and was on the bottom of the bucket.

 

[adambrum]

I took a different approach i fed it ! eventually he came right out to get the food and then SQUISHED IT a bit brutal i know,the only thing is you get one chance then they learn not to come out.