It should be veasible to build a ATS that pumps above the tank and flows right but in to the display, espesially on a Nano 29g. My canopy is 6" tall, so I am thinking of placing an internal pump in my display and having that feed some PVC to a 3x4" screen. Won't be seen for the most part. Ive done the google but have seen any true ATS builds above the tank. If anyone has any input or a design it would be appreciated.