If the 
Check
ink light stays lit and the 
icon appears above an ink
cartridge on the LCD screen, the cartridge is expended and you need
to replace it.
You may also need to replace a cartridge that is more than six months old, or if your printouts do not look their best, even after cleaning and aligning the print head.
The maintenance tank absorbs ink used in maintenance operations
such as head cleaning and switching between black ink types. Your
product contains two separate maintenance tanks. If the 
icon appears on one of the
maintenance tanks on the LCD screen, the tank is at the end of its
service life and you need to replace it.
Note: Please
dispose of your used Epson branded ink cartridges and maintenance
tanks responsibly and in accordance with local requirements.
If you would like to return your used ink cartridges and
maintenance tanks to Epson for proper disposal, please go to
epson.com/recycle for more information.