A slow or non-draining bathtub usually has a hair and soap scum clog near the drain opening. Remove the drain cover and extract visible debris with needle-nose pliers. Use a drain snake inserted 2 to 3 feet into the pipe to break through deeper clogs. Baking soda and vinegar followed by hot water dissolves minor buildup. A plunger can also dislodge blockages. Prevent future clogs by using a mesh drain cover to catch hair.