Sorry I cant help with ID, seems like Haley nailed it. I did have one similar to yours, but it had orange markings. I forgot what it was called. Anyhow, seems they like sand. Not sure if you have him in qt now, but sand in the future.
I uploaded 2 pics. they are huge , I didn't edit before hand. GL
http://www.reefcentral.com/forums/pi...ictureid=79225
http://www.reefcentral.com/forums/pi...ictureid=79226