Is the tub in a rack? If so I think you could move her up to a 28 qt. without any trouble. If it's just a loose tub, you might have to clutter it up with some crumpled newspaper or fake plants to block some of her view and make it feel like a smaller enclosure if she starts acting stressed. My 100 gram baby is in a 38 qt. and she's doing just fine, but she's in a room that has barely any traffic at all, so...