Keep the Toilet Bowls Clean
Does your toiled bowl have stubborn stains? It is apparent that you’d like to clean it, but none of the special cleaning products seems to work on that ugly junk. To keep the stains from becoming permanent on it, use WD-40. Wet the area with stains with a spray, and then let it sit and soak the product up, just by waiting for a few minutes.
source: science101.com
As the substance will settle down on stains, it will break down the gunk, and then you can scrub the area with a toilet brush. Moreover, it will also prevent any future debris from sticking along the sides. Once you have cleaned with WD-40, you can complete the cleaning with the products such as vinegar, bleach or plain soap.