Many individuals face consistent toilet bowl stains despite properly cleaning their bathroom ... bathing soap and caustic soda. Caustic soda is the chemical compound sodium hydroxide (NaOH).

Caustic soda (sodium hydroxide) - 1 cup, Hot water 4 to 5 cups, Gloves - 1 pair Cleaning brush or sponge - 1 Water-filled bucket - 1 Kitchen towel - 1 First, wear gloves and avoid touching your hands.