7. Lift the spreader. Wait at least 1 minute for the gel to solidify (fig. 7).
Figure 7
8. Incubate plates with the gridded side down in stacks of up to 20 plates.
Incubation time and temperature will vary according to the application
and equipment available.
9. Colonies on Petrifilm plates can be counted on a standard colony
counter or other light source (fig. 8). Bacterial colonies on Petrifilm CC
plates are red because of the indicator dye in the medium. Refer to the
Interpretation section on pg. 8 and 9 for more details.
Figure 8
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