Hi I am Mark Williams and on behalf of Expert Village and the producer of this series you can visit our website at www.williamspictures.net. What you got to do you got to drain out the whole water in the bowl. Do not flush after you do that because you are going to have drain all that water out as well. Drain out all the water in the bowl. Take a gallon of these stuff. Unscrew the top. Do not forget eye protection on this one. It is very important because it can splash back and don't forget your gloves. You open up the bottle, you pour the entire gallon into the empty bowl and it would fill up, you want to close your lid, close the other lid, and leave it for three hours. You would come back and you would just flush it like normal and it would all be done. The lime comes from urine which is not flushed on a constant basis and the minerals in the urine build up over the years cause restriction in the toilet. Clogging, plugging, and it is just unsitely. Rust comes from high iron content water and the rust usually forms around the water level of the toilet. We are going to go through and learn how to remove this properly you need to be particularly careful on china not to scratch it or break it for that matter because the more scratches you have in there the more places you got for collection of these minerals and rusts.