The ink monitor may show "Low ink" when the Canon PG-240 or CL-241 cartridge is being installed. It may also happen after printing a small quantity of pages(10 pages, 20 pages, etc).
The reason is that these inks are remanufactured cartridges, the chip had saved the information of the original cartridge.
Please PRESS "STOP" button on the printer panel for over 5 seconds for some models, the printer will ignore the low ink message and should now print without any printing or quality issue.
Please see attached file for the more details.