get some filterfloss or sponge from a friend tank if possible lfs have ich too sometimes,take a scoop of sand from another tank too just for the bacteria,.
i would leve the tank for mabey 3 days do a waterchange add mabey half the fish if you can catch them easily wait another 3 days waterchange and add the rest of the fish and start coppering,
if the fish are showing alot of ich i would move all 5 after the first 3 or 4 days and start coppering.
http://www.reefkeeping.com/issues/2003-08/sp/index.php
http://www.reefkeeping.com/issues/20...ture/index.php