1 A do-it-yourself approach for basic basement steps starts around $250-$350 for materials, and takes about 3-4 hours. 2  That's with standard lumber, such as pine; costs can go much higher with more expensive wood, such as oak.
Pour enough melted agar into each sterile plastic petri dish to cover the bottom - about 1/8 to 1/4 deep. Replace the lid immediately. Place agar plates on a counter top to cool and set. Agar medium will set like stiff gelatin at room temperature. The agar medium is now ready for storage or use.
An agar plate is a sterile Petri dish that contains agar plus nutrients, and is used to culture bacteria or fungi.ncubation of agar plates [edit]. Plates are incubated upside down to prevent drops of condensation collecting on the inoculated surface. Some plates are incubated at 37Â° C in a 5% CO 2 atmosphere: the temperature and conditions at which some of the body's bacteria will grow.