Acid Cleaners
Acids help remove hard water deposits. Some acid cleaners help remove discoloration from aluminum, brass, bronze, and copper. Other acids remove iron rust stains. Acids are typically found in toilet bowl cleaners, rust removers, metal cleaners, and kitchen and bath cleaners that remove mineral products.
* White vinegar, a weak acid, is about 5 percent acetic acid. It may remove hard water deposits from glass, rust stains from sinks, and tarnish from brass and copper.
* Lemon juice, another weak acid, contains citric acid, which can be used in much the same way as vinegar.
* Oxalic acid is effective as a rust remover.
* Phosphoric acid is often found in cleaning products that remove hard water deposits.
* Hydrochloric and sulfuric acids are sometimes used in diluted concentrations in toilet bowl cleaners.
Rust stains present a special problem on plumbing fixtures. Commercial rust removers contain oxalic acid. If you purchase oxalic acid at full strength, dilute it with 10 parts water. Follow all precautions when using oxalic acid, as this is a highly toxic product. A commercial product like ZUD may be effective on rust stains because it contains oxalic acid. When surfaces have become rough or pitted from repeated scrubbings with an abrasive cleaner, ZUD or a similar product may be mixed with water to form a paste and left standing on the stain for several minutes, then rinsed off.
For fixtures that are not acid resistant, clean with trisodium phosphate to remove the rust. Cream of tartar, a mild acid, may be mixed with water to form a paste rust remover.