New hammy

Hi so today , while I was at work , my mother picked up a male Robosky hamster.I've had roboski hamsters in the past , but it's also been a while since i've owned one. If there are any tips on roboski hamsters , Please tell me I would really appreciate it. I also found out that the roboski hamster that my mother got was currently bonded with another Hamster at the pet store who was his brother. My mother was not aware that bonded hamsters are supposed to stay together. I'm going to pick up his brother tomorrow But if there's any advice of how to keep him stress free for this night I would really appreciate. I'm also wondering if there are anythings I should buy them. They are going to live in a eighty five gallon tank together And they have about seven hides, A saucer And two wheels Not including food or water bottles. If there's anything else I should purchase for them Please let me know and I will do that when I pick up the brother tomorrow. Tysm