Dear Uncle Dixer: Does a bed facing sliding doors that overlooks a pool affect Feng Shui? If so, are the effects positive or negative? 

Answer: A bed facing sliding doors overlooking a pool does affect the Feng Shui of the room. Whether its effects are positive or negative depends on what you do.

During the night when you are asleep, the sliding doors should be closed and the curtain drawn. They can be open when you are awake or reading in bed. The view of the light-reflecting water is considered auspicious in Yang time but not during Yin time.