Got mine a while back they're great little guys, be sure to feed em so they don't feed on your plants.
I sprinkle crushed oak leaves in the vivariums every month or so for them to "process", helps fertilize the tank too.
If you have crabs (LOL) they will eat Isopods, I can't keep them long term in the Geosesarma crab tanks they all get munched before they have a chance to settle in and breed. But they are probably a healthy live food since they spend a lot of time on the cuttle bones. Geos are mainly carnivorous though so maybe hermits would leave them alone? Whatever you plan to do with them I would suggest setting up a separate culture bin for them to breed in and transfer the offspring to the individual vivariums this way you have a steady supply to account for old age deaths, and getting eaten.
My bin is just a 15 quart sterlite with 2 inches of moist peat moss (not sopping wet) egg crate pieces (makes easier to transfer them to other tanks as they like to hide up under the cool moist cardboard. Every month or so I add leaves and a quart of water to rewet the soil to stay moist/damp. This is how it looked the day I started it: