ky1974,
Small waterfalls generally don't require a liner. It's always a good idea to seal the bottom of any waterfall with several coats of thoro-seal or similar product to prevent leaks. Good luck.

Great that he is sloping the pad, I always do that with features that I build. I always seal the base of a waterfeature with either waterproofing materials (thinset, Dec-O-Shield is a good one) or similar products. In this case if the feature should leak it will leak back into the pool.
Heres to a good job well done.

Thanks.

I assume you are taking abount sealing the base of the bond beam/pad not the rock itself, right?

Looks like Dec-O and thoro-seal have a lot of different products. Can you suggest one ?

thanks again.

Just use pool mix and some portland cement or some portland and mason sand mixed a little heavier on the cement.

See ya,
Kelly

And add some Xypek in the mix.