Hello All,   Attached is a diagram of a new system I'm building. Comments and suggestions are greatly appreciated.   I modeled the system off a CHOP2, with the addition of an elevated head tank to gravity feed the towers and growbeds, and to also provide a solids waste tap. The bulk of the system will be enclosed in a 13x20' climate-modified (not climate-controlled) greenhouse. A 300 gallon sump…