So very sorry this is happening to you. I have heard of sugar water maybe not that much. I always used a 30 gal. Storage container at first with red bulb like yours till they out grew that one I worry a smaller bulb might not keep her warm and she doesn't have other ones to snuggle with 90-95 f is a must. Please do yourself a favor leave the marbles in waterer I almost lost one on second morning she was weak like yours and got in waterer, got wet and chilled found her next morning almost dead but she was saved from that only to die the next day because I separated her and I believe I overheated her your girl is weak right now I don't want her to have same problem mine did leave marbles for 4 or 5 days till she can get about easily. I have ordered from metzers a couple of times im in virginia so cross country they arrived wed. am and i got the grow gel they are good to deal with let them send you replacements bc she will need some friends. It sounds like you did everything just right in perpetration so don't beat yourself up sometimes in nature they aren't meant to thrive or it could have been a bad hatch praying she makes it threw ducklings are a lot of fun.