say my grow bed is 4 x 8 x 1 ft. It has a liner. Now what about building a steel wire mesh grow bed that would support and hold the gravel and its dimensions being just under the size of the interior main wooden grow bed where by which the wire mesh box would sit within the wooden box ( think of a strainer within a pot ) and allow air circulation around the sides and under gravel bed. All sides of gravel bed would be exposed to air. Still incorporate the flood and drain concept with an over flow and a bell syphon and possibly a fan positioned to enhance air flow underneath and around sides of mesh bed ? Also using larger diameter media to allow for said better oxygenation of root system ?