I am following Peter Reinhart's receipe for Seed Culture/Starter (page 38: Artisan Breads Every Day). Phase 1 went well. I went on to Phase 2 the stage that is supposed to take from 1-4 days. I noticed yesterday that when I stirred it it was foamy underneath the surface, but smooth on top (no bubbles). I waited another two days and now I am down to a very liquid state and no foam. Did I wait too long? Is the room to cold? What are next steps from here?