Set up your waterfall and get some PVC pipping from Home Depot. Cut it in half length wise and silicone it together to make your "river" I saw something like it on another page (and of course, now I can't find it again) and they had it covered with river rocks to hide the pipe.
Just thought I'd pass the idea on to ya.
-----
Heather 

Chilean Christmas Toad
(B.Varigatus)


