A container (1) with separate sealed compartments for different substances. The container (1) comprises separate and relatively sealed first (A), second (B) and third (C) compartments. The first compartment (A) receives a first substance (such as colorant); the second compartment (B) receives a second substance (such as a developing solution); and the third compartment (C) defines a mixing volume for receiving the first and second substances from the first and second compartments. A rupturable portion adjoins the third compartment (C) and separates the first and second compartments (A, B), from the third compartment so that in use, when the a rupturable portion is ruptured substances from the first and second compartments (A, B) can pass to the third compartment (C). A passage (16) is provided in a wall of the third compartment (C) along an edge not shared with either of the first or second compartments. The passage (16) leads to a first opening that is opened by a first opening means (6) which when opened, permits controlled release of a user defined amount of the first and/or second substances; and the third compartment (C) has a second opening with a second opening means (66) which enables at least one of the sheets to be opened in order to access the third compartment (C) and remove first and/or second substances therefrom.