✦ Starter Troubleshooting ✦
That sharp chemical smell is acetone, and it means the same thing hooch does. She's hungry, and she's been hungry for a while.
A well-fed starter smells tangy and a bit yogurty. As she runs out of food, the smell sharpens through vinegary and into solvent. It's a hunger scale, not a warning.
What to do. Feed her. If the smell is strong, discard down to a small amount first and feed at a bigger ratio, something like one part starter to five parts each of flour and water. That gives her more to work with and dilutes what's built up.
She should smell pleasant again within a feeding or two. If she doesn't, feed twice a day for a few days.
Worth changing. This is a scheduling problem, not a health problem. Feed more often, feed at a bigger ratio, or keep her somewhere cooler.