Just a little update. My DT was and is infected with ich. It shows no sign endless I put the PBT in. Once the PBT or achilles go in, the is a brake out. When the tangs are removed, the ich disappears. I can cure the tangs, put them in QT for a month, and then put them back in the DT and voila, the ich shows up again.
I must have had a fish that never showed ich in QT come in as a carrier. I began treating my DT on 08/09/2014 by removing and treating my achilles and PBT tangs with the transfer method.