Mine wouldn't eat for a few days when I first got it, but now it eats fine. It also went through a few days looking just awful, where I swore it was going to die, but looks great now. I don't think it liked being shipped. They just need some time to acclimate themselves. As long as your water quality is fine, don't worry about it. Also i wouldn't worry about the sand. Maybe blow it away with some current; otherwise I'm sure it will get rid of it itself.