I got Bella when she was 13 weeks old, she pooped in her cage on the way home and was covered in it, so she got a bath about 2 hours after I got her, lol. She was just fine.
Bella gets fed 1/4 cup of food twice a day, she inhales it, and pretty much never chews any of it (which I hate, but there is no stopping her). If we left it down all day, she would be ridiculously obese.
Amanda and Bella