White Watchman Goby
This is a typical pose, sitting on top of some plant or rock; in this case, it was turtle weed.
A view from up front; he is very tame, coming up to the glass often, and even allowing me to scratch his sides and belly at times.
Another shot, at a time when I was having a serious red/brown scum algae problem. In the upper left you can see a feather duster head; to the left, a plate coral (with pink tipped polyps) which is dying off (notice the algae edged stony plates on the left center; and an anemone on the right (I think).
Here he is again, wandering among the brown mushrooms.