Does Kefir need a breathable lid?
Kefir functions best when it has oxygen. When you try to go anaerobic (no oxygen), you will be getting basically a carbonated kefir wine. Some people prefer to ferment with a tight lid to increase the carbonation (though this can be done at a later process). It also increases the risk of explosions when the lid is tight. We always ferment ours with a cloth of some kind as the lid.
