B O D l o a d i n g = 20 , 000 L d a y × 187.5 m g L ÷ 1000 2 = 3.75 k g d a y {\displaystyle BOD\ loading=20,000\ {\frac {L}{day}}\times 187.5\ {\frac {mg}{L}}\div 1000^{2}=3.75\ {\frac {kg}{day}}}