Do I have to remove peels or seeds?

The rule of thumb is: If you can chew it, you can juice it.  So, most seeds, apple peels, pomegranate arils, etc., are all okay.  Definitely don’t remove peels if they are thin or soft because the nutrients are sometimes more potent in the peel.  However, you wouldn’t chew on lemon rind, pineapple rind, or peach pits, so don’t juice them.