Most folks that fill from a well have iron in the well water. When you add large doses of chlorine to water with iron in it, the iron can precipitate out and cause brownish or orangish staining of the water and/or liner. If you've added bleach to get up to 9 ppm with no browning of the water, you may be one of the lucky ones. If you do start to see browning of the water, then you'll need to add some metal sequestrant to keep the iron suspended in the water. Do you have brown or orange stains in your toilet tanks?

When you put chlorine in the pool, some of the chlorine combines with the "nasties" in the water to sanitize them. This is registered as CC. Once your CC gets to 1 or above, then by shocking the pool you're adding enough FC to overcome whatever the "nasties" are in the water, and you should see the CC go back down to zero, which is where you want it to stay.

Does that help?