Storage assembly for two substances to be mixed prior to use, comprising a closable dropper tip (3). A first storage chamber (7) is formed by the closable dropper tip (3) and a first container part (2, 4), the first container part (2, 4) being provided with at least one aperture (43). A second storage chamber (8) is formed by a second container part (5) which comprises an open end part (52, 53) that closes off the at least one aperture (43) in a first operational position. The first and second container part (2, 4; 5, 6) are moveable with respect to each other, and are in fluid communication through the at least one aperture (43) in a second operational position wherein the total flow surface area of the at least one aperture (43) is at least equal to a cross sectional area of the first container part (2, 4).