Opinions wanted on concept

[Ray]

I have a 20-gallon high aquarium that I am thinking about setting up for jewel orchids.

Here's my thoughts on the concept, so far:

Back - EcoWeb with automated watering from the top. I'll probably get some green moss established on it.

Bottom - a layer or two of EcoWeb, covered by sphagnum as the growing medium.

The idea is that the bottom will have a "standpipe" to keep the water depth no higher than the EcoWeb base, allowing the sphagnum to be watered by wicking from the bottom, keeping it loose and airy.

The stand pipe would drain into a small tank in the stand underneath, containing a submersible pump to periodically wet the back wall and refill the bottom's loss to evaporation.