145 mmol/L (3.345 g)(1mmol/L = 1mEq/L), and potassium makes up most of the cell fluid cations at about 150 mmol/L (4.8 g). Plasma is filtered through the glomerulus of the kidneys in enormous amounts, about 180 liters per day. [ 59 ] Thus 602 g of sodium and 33 g of potassium are filtered each day.