About how much milk does a lactating blue whale produce in one day?

Information from the Marine Mammal Center states "Females give birth to calves every two to three years. They remain pregnant for about one year before giving birth. When born, the blue whale calf is about 23 feet [7 metres] long and weighs 5,000 to 6,000 pounds [2,268-2,722 kg]. A nursing blue whale mother produces over 50 gallons of milk a day. The milk contains 35 to 50% milk fat and allows the calf to gain weight at a rate of up to 10 pounds an hour [5kg/hr] or over 250 pounds [113kg] a day! At six months of age and an average length of over 52 feet [16 metres], the calf is weaned. The blue whale reaches sexual maturity at around 10 years of age.