Organic Oxygen and Water Vapor from plant transpiration
This wall system presents a new opportunity for horticultural experimentation. The wall can be filled with peat moss or other hydroponic medium. Wastewater enters into a perforated pipe along the top and percolates down to the bottom. Plants grow horizontally out of the wall with their roots intermingling in the wall cavity. The dense combination of different microbes from appropriate plants may be highly efficacious for water treatment. This idea was first brought forward by a NASA scientist developing options for water treatment on Mars.
https://en.wikipedia.org/wiki/Constructed_wetland
The eight square footprint of this construction supplies 192 square feet of plant growing area. The roots would concentrate into a volume of 43 cubic feet. There is no reference to this concept having ever been tried before. Interior plants are a great way to maximize organic oxygen and water vapor for one’s health.
Outside hardscapes can be built however high for landscape architecture. Perforated pipe can feed wastewater (aka nutrient solution) along the length and root microbial activity can clean the water seamlessly exiting the building .