Salt in the soaking water, took me a whole bag to learn that one.

Are you sure it's not just a rusty arcade token?

Power outages always seem to mess with the tiny routines we don't think about until they break, and a starter is a perfect example of that. Eight hours at room temp usually just makes it hungrier, so the clear liquid and grainy bottom are signs it ran out of food, not that it died. Keep feeding it twice a day and it should bounce back in about a week, the acid smell fading as the yeast wakes up again.