Update: Found another shed today! Counted everyone but one again - pretty sure the one that molted today was the one who's been visibly getting ready to molt for a few days. He's almost completely translucent today (usually is a solid red with a racing stripe), moving kinda slow, and seems to be bothered when other shrimp get close to him. I'm pretty sure he's male now that I can see through him, no signs of a saddle or anything. So I'm hoping the one who molted yesterday and is hiding is a female - maybe they feel more vulnerable dealing with eggs? Hoping for babies!