Dry potato dextrose agar mix. Frequently used in the expansion and isolation of mushroom mycelium. 114 grams (1/4 lbs) per container. 20 grams per 500 ml of water to fill (20) 100 X 15 petri dishes.
Heat water to a simmer and add potato dextrose agar mix. Simmer and stir slowly until fully dissolved. Sterilize at 10 psi for 30 minutes and pour.