Trace2O AquaSafe WSL25 Plus, Instruction Manual

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When all the water has been filtered, release the vacuum pump and use the
sterile forceps to take the membrane from the filtration unit.
Place the membrane on top of the pad, which has been previously saturated with the MLSB
media.
Replace the petri-dish lid and mark the petri dish. A suitable system should be adopted to
record the petri dish mark, associated with the sample number, place, date, time, etc.
Place the petri-dish into the rack. Repeat the process for all the samples and then place the
filled rack into the incubator.
It is important to note that when the last sample has been processed, a resuscitation period
of at least one hour (but not more than four hours) must be observed before incubating.
This allows any physiologically stressed coliforms to recover before culturing.
To incubate faecal (thermotolerant) coliforms, temperature of 44.5°C should be used. For
total coliform analysis, a temperature of 35°C is appropriate.