Heed REA17's advice. Use Cupramine for the treatment and remove the rock before you add the Cupramine and while you are treating with Cupramine (or any copper). The rock will remove the copper from the water and you won't have a proper dose of copper to treat the fish effectively.
Also use PraziPro to treat for flukes.
I get the fish eating well, then do a PraziPro treatment, water change, start Cupramine (ramp up slower than the directions on the bottle - 1/3 dose on days 1, 3 and 5 or 1/4 dose on days , 3, 5, and 7), do another PraziPro treatment, remove Cupramine from the water after 4 weeks, and observe another week or two. Total quarantine time is typically 6-8 weeks.