I recently purchased 3 bottles of 36mg Nic in PG (120ml each) from Good Prophets. It has been a few weeks and I've only used half of one of the bottles. It has made 135ml of juice for me @12mg, so I am set for awhile. But, my concern is, at what point do I need to freeze the nicotine? Will it go bad if I leave it sealed in a dark, cool area? Also, what happens if nic "goes bad"?