I just got 2 new aros, both are about 5 inches. Anyways they'll both settle on the bottom quite often. I think its because right now they are in an 18 and don't have much room at the top. (Just picked up a 55 yesterday to move them to). Anyways, what size is your tank? That might be the reason. Other than that my aros appear fine, eating and what not. I'm no aro expert, but thats what I've observed with my aros. We'll see if their behavior changes when they get the bigger tank.