cleaner in order to protect your pipes from corrosion.
remove a clog by hand. take off the strainer or stopper by unscrewing the edges or popping it off. shine a flashlight inside the drain and look inside. you may see a clog right at the surface of the drain. if that is the case, put on some rubber gloves and then reach in and remove it with your hand. if you can’t see anything, then the clog is probably deeper and will require a tool or chemicals to remove or break down.
contact a plumber. if your drain repeatedly clogs and nothing seems to help, then go ahead and call a plumber. 