Printing apparatus, printing method, and medium

A printing apparatus comprising:

• a liquid ejection head including an ejection opening ejecting a liquid, a print element for generating energy for ejecting a liquid, and a pressure chamber having the print element provided therein;
• a buffer tank for storing the liquid to be supplied to the liquid ejection head;
• a main tank for storing the liquid to be supplied to the buffer tank;
• a supply path for supplying the liquid from the buffer tank to the liquid ejection head;
• a collection path for collecting the liquid from the liquid ejection head to the buffer tank;
• a circulation unit configured to circulate the liquid inside a circulation path including the buffer tank, the supply path, the pressure chamber and the collection path;
• a prediction unit configured to predict a value relating to concentration of the liquid inside the circulation path on the basis of a discharge amount of the liquid discharged from the ejection opening;
• a discharge unit configured to perform a discharge operation of the liquid inside the circulation path on the basis of the predicted value;
• and
• a replenish unit configured to replenish the liquid inside the main tank into the buffer tank on the basis of an amount discharged by the discharge operation.