I don't have any filter on my bags - do I need an air exchange for the mycellium to grow? Reading through the various teks (like PF, for example), the containers were sealed while mycellium grew out. I figured I'd leave them shut based on other tek's instructions. From here, I'm planning on following Lazlo's fruiting tek in this post using the popcorn spawn:
http://forums.mycotopia.net/showthread.php?t=19704 (Cultivating Oyster mushrooms on newspaper........)