Brewed up a a white IPA yesterday. It is my third time making more or less the same recipe. First batch didn't ferment down as low as I liked (stalled at 1.017). Second batch was money. I wanted to remake what I made that second time. All 3 batches I made a yeast starter (WLP 400). I used roughly a 1.2L starter of 1.035 wort. The ONLY thing I did differently, was I added some yeast nutrient to the starter during its 15 min boil. I had an insane amount of activity in my 2L flask while on a stir plate. I usually some sanitized tin foil to cover the top of the flask. It was so active that I did have some krausen spilling down the sides, but nothing major. Starter went for roughly 16 hours ( I usually go 20-24 hours). I pitched the yeast to my 70 degree wort yesterday at 2. We are now 27 hours later and I see no activity. How worried should I be? My bucket is in a chamber at 70 degrees.
Yeast production was 3/27 and I used MR.Malty's calculator for viability.