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.
5. Pour nutrient agar into each plate and leave plates on the sterile surface until the agar has solidified. 6. Replace the lid of each Petri dish and store the plates in a refrigerator. 1. It is frequently used for isolation and purification of cultures.2.. Pour nutrient agar into each plate and leave plates on the sterile surface until the agar has solidified. 6. Replace the lid of each Petri dish and store the plates in a refrigerator. 1. It is frequently used for isolation and purification of cultures.