-Saran Wrap (cut off 1 inch from the end of a roll)instead of Parafilm for sealing petridishes and test tubes.
Isn't the point of using parafilm is that it is a microweave bandage that allows CO2 to escape and oygen into the culture...but not the contams because it is microweave?! I would think sealing a tube completely off will slowly sufficate an attampt to store a culture.