I'm up in Vancouver right now and I visited a LFS. They have sand dollars for sale. I asked the owner if they were okay to keep in reef tanks and if they would survive and she said that they get them all the time and have never had any problems with them. She indicated that they are similar in nature to sandsifting starfish, ie, they burrow in the sand, stir it up and come out to eat once in a while.
So, how come no one ever sells these in Utah? Does anyone know anything else about them?