From experience 'ghost shrimp' eat pretty much anything you feed them (within limits..obviously!!)I feed them algae pellets, but they're not the smartest animals so often the fish pick up on them before the shrimp even realise they're there!But occasionally they'll get one...and that's pretty much all they need.They'll eat normal fish flakes too but the fish get them too quick!
If you get a group of them it should help make them less timid...but in nature they're preyed on by anything big enough to eat them so they'll always want to hide in the shade or plants or whatever.Often when the lights go out i see mine swimming about..which looks quite amusing,