Apparatus for mixing a fluid and a liquid

Apparatus for introducing a fluid into a first liquid, the apparatus comprising a first container for holding the first liquid, the first container having an opening closed by a releasable closure, and a second container located in the first container adjacent the opening of the first container;

• the second container comprising an outer housing located in the opening and an inner container containing a fluid, the inner container including a rupturable member and being movably mounted in the housing for movement between a closed position in which the inner container is sealed by the housing when the releasable closure closes the opening, and an open position in which the fluid within the inner container is released from the inner container into the first container and into contact with the first liquid on release of the releasable closure, the housing also including a rupturing member to rupture the rupturable member on the inner container.