Liquid ejection apparatus

A liquid ejection apparatus comprising:

• a first tank configured to store liquid;
• a first liquid flow channel configured for discharge of the liquid into the first tank;
• and
• a connecting unit configured to disconnect the first tank from the first liquid flow channel in a disconnected state and connect the first tank to the first liquid flow channel in a connected state, wherein:
• the first tank includes a waste liquid port for discarding the liquid stored in the first tank and a cap for closing the waste liquid port,
• the cap includes a liquid discharging port for receiving liquid from the first liquid flow channel and an atmosphere communication port for exhausting the first tank to atmosphere,
• a downstream side of the connecting unit is connected to the liquid discharging port and an upstream side of the connecting unit is connected to the first liquid flow channel, to establish flow between the first liquid flow channel and the first tank,
• the atmosphere communication port includes an opening/closing unit configured to switch the atmosphere communication port between an open state and a closed state, and
• the opening/closing unit is configured to switch the atmosphere communication port between the open state and the closed state in conjunction with the connecting unit switching between the disconnected state and the connected state.