A multi-compartment resealable container for testing for the presence of micro-organisms is provided with or adapted to receive a sample in a first substantially rigid transparent compartment, a growth medium in a second compartment, and a sanitizer in a third compartment, the compartments being separated by foil seals, the second and third compartments have an associated plunger which when depressed causes serrated cutters to puncture the foil seal and allow the contents to be added to the liquid containing or comprising the sample.