So my sourdough starter is about two weeks old, but it suddenly stopped growing three days ago (after a couple days of very active growth)and developed a brown layer on top.The layer is mostly brown with about 15 percent of it being normal starter. Most of what I researched is that it is hooch, but the brown layer is more solid (the same thickness as my starter) and isn’t separate from the top layer of the normal starter. I have been keeping my starter in the oven with just the light on. As for my feeding schedule, I feed it 1 cup of AP Flour and 1/2 cup of water every day. If anyone has an answer, please let me know; it would very helpful.