I'm new to making sourdough starters and breadmaking in general. Following Katz's recipe, I used 2 cups freshly ground spelt and 2 cups spring water.
I put the mixture in a quart jar, covered with cheese cloth and put in the oven with the light on with a thermometer in there. The temp has been between 70-85F. In the first 24 hours, it started to rise and bubble quite a bit. This was much sooner than the "number of days" Katz says is common than I expected. It rose to larger than the quart jar could handle and it poured it out into a large ceramic bowl. All the while I was stirring 2x/day the first day then several times a day since then.
It's been about 3 days since starting it (I'm in Seattle) and since that quick burst of bubbling/rising I have seen no bubbles. It certainly has a strong sour smell.
My question is, is now the time to start feeding the starter? Was the quick bubble action the sign of it being active and just did so quickly because of the warm temp in the oven (it was 80-85F the first day)? If I wait too long to feed it, will it "die" or go bad?
I've since propped open the oven door, which has brought the temp down to 70-75F.
Thanks!