With your fish josh, you need some decor to break up the spaces, so the fish have somewhere to call their own, they are territorial fish and if you leave the tank completely bare you are asking for trouble.
If the fish retreat when you walk it, its because they are new to the tank (youve only had them a week or so) and are not yet used to movement, Im guessing there isnt someone there all day to create constant movement, so when you go into the room it startles them and yes they will retreat. In time they will become used to it, especially if as said, you give them a small treat when you enter the room, until then, can you leave a TV on near the tank so there is some form of constant movement, even the flickering of a TV could make a difference. Also give them time once you have entered the room before turning on tank lights, again so its not a shock to them.