[sami]

when i first got mine, they hid for quite a while too. sometimes they burry themselves to destress. I had gravel before too and as soon as i switched to sand, they became a little (but not much) more active. you could also try to put a treat they favor in the food dishes. U could try Freeze dried shrimp, krill, or plankton if you havn't already. I wish you luck with your hermits