The Ozone reactor works by mixing the water and ozone in a reactor ... using the wet and dry method, with reverse flow to allow greater contact time between water.
 
The O3002 should be situated in cabinet below aquarium or In or Next to sump.  
 
Kit includes:
O3002 Reactor,  Carbon Reactor, Carbon Media, 12mm control valve, 12mm flexi piping (2m)
 
Water Pump requirement : 500lph - 800lph
Air Pump requirement : 300lph
 
Hosetails: 
Inlet 12mm and Outlet 12mm on both the Ozone and Carbon reactors.

Dimensions
Height              : 600mm
Footprint        :135 x 135 mm
Chamber Dia: 90mm