well sometimes they like to poop in their hides, so i do lift their hides and check them. They are mostly around 500g. Some of them have been off feed for 2 months and some for 1 month. I know it's not a big deal for them to go off feed, but it will be nice if they can start feeding. i breed my own rats, so i'm getting a bit overwhelm with all those grown up rats. When I put the rat in their tub, they just don't seems interested or just get scared when the rat sniff them. My temperature are all right with 80 cold side and 90 hot side. All their hide fit pretty well. So i really am not sure why they go off feed. I will just leave them alone for about 2 weeks and hopefully they will feed soon.