baking soda & white vinegar to unstop drain. pour 3/4 to 1 cup of baking soda in the drain. ( real saver use the baking soda that has sat in your Frigidaire deodorizing it , down) Next pour 1/2 cup white vinegar in the drain, but quickly stop up the sink with the plug or a plate over the drain. Wait 30 mins. then run hot water for 2 or 3 mins. down the drain. Do on a regular basis of about once a month to keep drains fresh and clear without any problems.