To dream of a bathtub represents a positive or comfortable mindset as you get rid of problems. Feeling good or enjoying yourself as negativity or conflict is dealt with. Feeling good about situations where you are effectively controlling problems. Effectively managing emotions.
Alternatively a bathtub may reflect self-reflection over issues or problems you have as they are being cleansed from your life.
To dream of seeing a bathtub where the water turns red may reflect a relaxed attitude towards problem solving that has turned emotionally dangerous. Feeling that you may have made a problem worse by being too casual about confronting it.
Example: A woman dreamed of having her bathtub ripped out of her house. In waking life she had just had knee surgery and found doing chores or taking personal time for herself to be extremely difficult since she couldn't bend over.
Example 2: A woman dreamed of being in a bathtub with water that suddenly turned all red. In waking life she was feeling good having finished dealing with a problem in her life when suddenly her menstrual period started.
*Please See Shower