? on arco crabs

[easygoer2]

Just brought a new acropora home and it had an arco crab in it. I have a few questions on them. This is my first one. Are they good or bad. If there good, what for. Will it eat the corals,snails,ect? Got this at the LFS. Does this mean that the coarl was'nt tank raised? If I need to get him out it looks easy. He just sitting in the coral.
easygoer2

 

[hurley675]

Yes they are good

I got my first a couple of weeks ago and he is awesome.

What they are good for is mainly for defending the coral.

For example if the algea or nori i put is in the tank and it gets away on accident and goes towards the acro then the crab will reach out as far as it can and try to get it out of the acros terrotoiry.

Another example is in the wild when a crown of thorns starfish (eats corals)is coming over the coral they will start attcking the star fish. So this a nice addition to the tank