I’m completely new to brewing my own beer. I’d like to know whether i can cover my fermentation container with an airtight seal, because its not the greatest of smells to have lingering in the house for 3 or 4 days. Does gas need to escape i.e. does it affect the fermentation process, i know that most microscopic organisms die in the absence of oxygen, is it the same fo yeast, or can i get away with putting a tight lid over it?