Coppersafe doesn't need you to remove the filter or the filter pad or the carbon. Just leave your filter as it is.
The active ingredient in CopperSafe isn't removed by carbon, only through water changes.
I've had a lot of success with it for treating ich. However, I never add full dose at one time, I always add 1/4 dose every 4 or 8 hours, just in case the fish get a bad reaction.