The toilet is one of the most utilized fixtures in any home. Over time, hard water, mineral deposits and grime in general can stain a toilet bowl. General cleaning products and a scrub brush are not enough to clean these types of stains and, unfortunately, many people find themselves replacing their toilet needlessly. Muriatic acid can restore a stained toilet bowl to a like-new luster in mere minutes, as long as it's used properly.
Turn off the water to the toilet by turning the small valve, located on the face of the pipe that runs from the toilet tank to the wall, all the way to the right. Plunge out as much of the water in the bowl as possible.
Put on your eye protection and your rubber gloves. Given the caustic nature of the acid, using personal protective equipment is a must for this project.
Pour the muriatic acid into the toilet bowl. One third of a gallon should be more than enough to remove mineral deposits. You may use as much as 1/2 gallon for heavily soiled toilets. Allow the acid to set for two minutes.
Scrub the toilet thoroughly with a scrub brush. Leave the brush in the bowl and sprinkle 1/2 box of baking soda around the edges of the bowl, on the brush and in the water to help neutralize the acid.
Lower the lid of the toilet bowl and turn on the water to the tank. Allow the tank to fill and flush the toilet several times. The flushing water will neutralize any remaining acid. Finally, lift the lid and remove the scrub brush.