The rest will follow suit soon enough
Give them a little bit to settle they've been through alot. They'll be out and begging in no time. They're in good hands, I have no doubt that youll end up with a nice male out of that group.

Happy they're eating at least.
I think they're just smart fish - they know they're small and that they should hang out under cover so they don't become a snack.
Can you dim the light or maybe throw something in there that floats to give them some cover from above so they feel more secure?