Liquid discharge apparatus having tank to communicate with cartridge to be attached in the apparatus

A liquid discharge apparatus comprising:

• an installation case configured to be attached to a cartridge;
• a tank including a chamber, the tank further including:
• a first channel including one end in fluid communication with an outside of the tank and an opposite end in fluid communication with the chamber, wherein the first channel is configured to form at least a portion of a channel providing fluid communication between a cartridge chamber of the cartridge and the chamber when the cartridge is attached to the installation case;
• a second channel including one end positioned below the first channel and in fluid communication with the chamber;
• and
• a third channel including one end in fluid communication with the chamber and the other end communicated with the outside of the tank;
• a head in fluid communication with an opposite end of the second channel from the one end;
• a memory;
• and
• a controller configured to:
• receive a first discharge instruction for discharging liquid through the head;
• update a first count value by a value corresponding to a liquid amount instructed by the first discharge instruction;
• calculate a total liquid amount Vt by subtracting the first count value from an initial total liquid amount Vt, the initial total liquid amount Vt corresponding to a sum of a liquid amount Vc in a cartridge chamber and a liquid amount Vs in the chamber;
• read correlated information from the memory, the correlated information indicating a correspondence among a total liquid amount Vt and one of the liquid amount Vc and the liquid amount Vs;
• and
• based on the updated total liquid amount Vt and the read correlated information, determine the liquid amount Vc and the liquid amount Vs.