If you are incubating at room temperature, we recommend an incubation period of 36 hours. If you are incubating at 86-90 degrees Fahrenheit (30 degrees Celsius), we recommend an incubation period of 24 hours. It is acceptable to incubate Microslides for 48 hours or more, however, keep in mind that the longer the Microslides are left to incubate, the larger the colonies may appear on the agar surface. When large numbers of microorganisms are present, an extended incubation period may result in Microslides that are difficult to interpret due to confluent growth.