I want to properly use mouthwash to kill bacteria thru the night but i do not want any brown staining on my teeth. what wash rinse product to rely on?

Mouthwash: Brushing, flossing, and use of a proxy-brush is the best routine for maintaining a healthy mouth. Use of mouthwash is not effective in removing bacterial deposits, although they can be helpful in preventing excessive growth. Salt water, a mild hydrogen peroxide solution, and baking soda may be just as effective as any store bought mouthwash. Concentrate on mechanical debridement.