Originally Posted by PeteM
The pump is the only part that stays submerged?
Yeppers, the skimmer itself hangs, in its entirity, off the back of the tank. The only other part in/near the tank itself is the output return, a ramp where the water flows back into the tank, but it barely touches the surface of the water.
AquaC also makes a two-chambered box that goes in the tank, one encasing the pump and the other recieving the output of the skimmer, which is then returned to the tank through a hole in the bottom of the box. This serves two functions . . . it ensures that the water entering the skimmer is only from the surface, and it cuts back on microbubbles from the output.
Interestingly, I ran mine without the box for a while, but once I put it on I found it much less visually offensive than just the pump. Unless the white lights are on, it really blends into the black background and the flat sides don't impose on the aesthetics of the tank like a pump dangling there.