Tuxedo urchin not moving..

So i have heard great reviews about these urchins and definately researched them a lot before purchasing. However as i was getting some saltwater from the store the other day, I noticed one (i havent found any local in a while). He was $24 so i decided to pick him up. Awesome colors and was very strongly attached to the wall of the tank. He was carefully taken off and acclimated to my tank over the course of an hour drip method. He moved from the sand bed last night and crawled up the side of my tank and now he is back on the sand bed and not even moving ANY of his spines/arms. Is this normal??? I hate to have wasted $25....

 

and i definately just saw the top off the urchin expell a bunch of waste (detritus im assuimg). I'm also assuming the mouth is on the bottom and the A%# is on the top.

 

That's a Tripneustes gratilla. And yes, the mouth is at the bottom and the anus is at the top.

It's not normal for them to remain motionless more than a day. It is normal for them to be relatively inactive during daylight hours, however.

I do caution, however, if this guy dies and you don't remove it, you may experience problems. Also, I wouldn't handle that one without gloves.

Bob Fenner on the species: