sea urchin

It looks an Echinometra spp. to me. You can find more information about them here. Saying that though, those are the sort of questions you need to research BEFORE buying a new tankmate.

As long as if you have plenty of rockwork for it to rasp on and I'd suggest a minimum of 50gal tank you should be OK. The are mainly herbivorous but will eat meaty foods. They need excellent water conditions.

They do drop spines but mainly as an indictaion to poor health/conditions.
 
ok but i have a 14 gallon tank will it be ok the people at the lfs said it would be fin and he looks fine
 
7 to 8 pund im going to the lfs tomoro should i get more or is that ok
 
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