DEF is contained in a separate tank; never fill a diesel fuel tank with DEF. DEF is consumed at roughly 3% of diesel fuel consumption. For every 100 gallons of diesel, 3 gallons of DEF are required.

Delphin DEF Dispensing Unit
Mounted on a sturdy trolley and complete with a 120V Electric Pump (1.6gpm), Tank (5gal capacity), Visual Level Indicator, On/Off Switch, 7ft. Delivery Hose and Fitting Connection.
Delphin Upper Tank 5 Gallon Capacity. Use with 55 Gallon Drum (NOT INCLUDED). Ships Unassembled. Packaged: 31in. x 42.1in. x 32in. 146 Lbs.