Microbiological testing of a liquid sample

A culture monitor for microbiological testing of a liquid sample, the culture monitor including

• a housing having a liquid inlet and a liquid outlet;
• liquid sample filtration means inside the housing between the liquid inlet and the liquid outlet, the liquid sample filtration means including a filter medium so that a liquid sample entering the housing through the liquid inlet passes through the filter medium, with microorganisms present in the liquid sample being retained on the filter medium and spent liquid or filtrate passing through the filter medium;
• a dehydrated culture medium located between the filtration means and the liquid outlet;
• and
• a reservoir in the housing downstream of the liquid sample filtration means relative to the liquid inlet, with a volume of a rehydration agent for the dehydrated culture medium being provided in the reservoir or the reservoir being adapted to retain during filtration, as a rehydration agent, a portion of the filtrate, the dehydrated culture medium being located such that it is sealed or separated from the spent liquid or filtrate during filtration at least until immediately after filtration of a liquid sample and such that it can be brought into contact with the rehydration agent, after filtration, to form a rehydrated culture medium for the microorganisms retained on the filter medium.