Love this idea...
But where do you get all the separate ingredients?
I mixed some ball clay (hit it with a hammer until it was dust) I had left over from my sculpture days into my dirt substrate along with the Miracle Grow Organic Compost and some expanded shale, then capped the whole thing with Floramax. Planst have been growing amazingly, no Co2 needed.
But I'll need ferts sooner or later... would like to make this!
So where to get the raw materials?
Also how do ferts in general impact your water quality, does it release nitrates, nitrates, etc into the water column?