A connection device for connecting a first reservoir with a second reservoir, includes a first section for arranging the first reservoir closed with a seal a second section for arranging the second reservoir and a piercing element which penetrates with a piercing end the seal of the first reservoir when the first reservoir is arranged at the first section. In some embodiments, the piercing element can be moved from a first position into a second position, wherein it blocks in the first position a flow connection between the first and the second section, while in the second position it allows for a flow connection between the first and the second section.
