Canon MG5100 series On-Screen Manual page 95

Important
Handle the ink tanks carefully. Do not drop or apply excessive pressure to them.
If the orange tape remains on the L-shape air hole (C), ink may splash or the machine may
not print properly.
Hold the ink tank with the orange protective cap (D) pointing up while being
(2)
careful not to block the L-shape air hole (C).
Slowly twist the orange protective cap (D) 90 degrees horizontally to remove it
(3)
off.
Important