Most parasites have a 12-14 day life cycle. Copper only kills Ich/velvet parasites during their "free swimming" stage where they are searching for a "host" to attach and feed upon. So 14 days in copper is cutting it a bit close and if doing this we suggest then to transfer the fish at the end of 14 days into a fresh QT and observe for 10-14 days to see if the parasites have been stopped or not. So for most a 30 day in copper is easier and perhaps safer to ensure the fish is parasite free. After the 30 days you will be spending a few days removing the copper with water changes, running carbon, and or a copper removing matrix like Seachem's Cuprisorb. While doing this, watch the fish for any signs of parasites. Sometimes a second round is necessary, especially if for some reason the copper dropped below therapeutic level.
After the copper, consider deworming the fish with General Cure. It contains both metro and prazi, and is easier on the fish than Prazipro. Two doses 5-7 days apart with a 25% water change before the 2nd dose. After the 2nd dose wait 5-7 days and you are done.