I found pots to repot my pilea. It was originally in a 4" pot, but there were a lot of babies in there (I split it into 7 total plants).The tallest I put in a bigger pot to hopefully be my main pilea to grow more babies. Literally overnight it developed black spots on some leaves. I didn't overwater since there was so much stress from separating the babies. I did move it near a window that has an air vent under it. Unfortunately all of our windows have air vents under them.What are these black spots? Do they get better or should I remove the leaves?