I made my own waterfall by using 2" PVC... The inlet was a U shaped
piece with a threaded hole that I screwed in a barbed connector then
on each end of the U I connected the 2"PVC pipe. I think its about 2'
long with another 2" U shaped connector at the other end. Then I used a
dremel or rotozip to cut a slit on one of the 2' lengths of the 2" PVC.
Hooked up my Pump and Hose and Viaola a nice sheet of water is a
flowing. I use a large 1250 GPH pump that I split off to my filter and
UV sterilizer. So not all flow is going to just the water fall but it
use to and was still a nice flow.

Good Luck,
Chris.

PS. If you want Pics I could post some what it looks like with water
flowing and without.