Hi
Usually they are slow waterfalls used to grow high moisture type epiphytes. The water "seeps" rather than falls
providing constant moisture and a boost in humidity besides very interesting to look at lol.
I started one in my shadehouse last March .My theory is to have grow areas from completely submerged to dry canopy
at the top . Sort of combining a terrarium with a greenhouse with landscaping .
the best example I've seen is Selby gardens where it is used mostly for orchids but is maintained in a controled environment. Fairchild is using one in the RPH.
Mine is coming along but i had several set backs from the weather.
I used a 150 gallon aquaruium for the water reservoir and expanding foam to make a "rock" wall. So far it's 10 feet wide and 8 feet up the wall.
gary

Pics, gary?

Hi
Have some but certainly not good ones. Don't have a decent camera and have been using the disposables.. The first disc I took during the layout came back blank.Have yet to get any underwater the flash bounces and can't get far enough away to get the whole thing in one frame. The growth on the wall has been incredible so now you can only see parts of it.. Added another 2x8 section at the top but was waiting for spring for serious planting.
Had to replace the roof and got some serious sunburn but looks like I'll only lose one orchid but sure got a setback
hadn't put up any pix as there's really not much to look at. Only serious planting has been to the aquarium which is doing great, though still a bit amber but getting there.
Wanted to be sure the heating system works before getting to "exotic" with the wall planting.
Someday it will be glorious though lol gary