To dream of a hot tub represents negative thoughts, emotions, or habits that are comfortable, pleasurable, or leisurely. Where as a hot water tank symbolizes very powerful negative thinking patterns that influence your life such as fears, a hot tub reflects more desirous or pleasurable negative thinking patterns. A common symbol for masturbation or viewing pornography. It may also reflect your enjoyment of situation that you know is wrong.
To dream of seeing sexually attractive people in a hot tub can symbolize your need to feel good with sexual fantasies, or masturbation.