Melanogaster Fruit Fly Media 1.5lbs, makes 10 fruit fly cultures. The #1 killer of fruit fly cultures is low humidity. Therefore, Josh’s Frogs Fruit Fly Media uses powdered potatoes rather than potato flakes. This not only allows for a more thorough mix of ingredients, but it also allows the media to hold more water. This keeps the media from drying out and prematurely killing the culture.