G&G genius ideas squad needed

Something to bear in mind is that it will take almost 380 litres of compost to fill a single tube (not cut in half).

I would try to figure out a way to turn them into water reservoirs which pots can sit in or on top of, like a very long, cylindrical Quadgrow. That would really cut down on the compost needed.

A big hydro growing system type thing, might be possible.