Acetic Acid

• Acetic acid is the active ingredient in vinegar, and it can ease the burden of cleaning even the most difficult toilets. Spray distilled white vinegar around the entire interior and exterior of the toilet bowl. Let it sit for 15 minutes and then scrub using a sponge (for the exterior areas) and a toilet brush (for the interior). Rinse the outside and flush.
  
  

Citric Acid

• Citric acid is effective for removing rust deposits and mineral deposits, two types of stains that often make toilet cleaning such a daunting task. You can find citric acid in lemon juice and in many powdered fruit drinks. Apply the citric acid to all parts of the toilet bowl (a clean spray bottle can make the job easy); wait 15 minutes and scrub away the stubborn deposits along the outer rim of the bowl.
  
  

Phosphoric Acid

• Urban legends dictate that cola soft drinks can remove difficult stains from toilet bowls, but this particular legend has quite a bit of merit. Soft drinks like Coca Cola, RC Cola, and Pepsi contain the ingredient phosphoric acid (as well as lesser amounts of tartaric acid and citric acid), a powerful rust remover. You can clean the inside of your toilet bowl by simply pouring a can of cola along the surface, waiting 10 to 15 minutes, and flushing.
  
  

Sodium Hypochlorite

• Sodium hypochlorite is the active ingredient in household liquid bleach. Its powerful chemical composition can dissolve stains on contact, but the product has some very abrasive qualities. If you want to clean your toilet with bleach, use commercial toilet bowl cleaners that contain bleach (the word "bleach" will appear on the label) for best results. If you want to use pure chlorine bleach, such as for mildew removal, dilute it heavily (1 cup bleach to a quart of water) and wear rubber gloves before your start scrubbing.