sorry to hear about the PBT, but we all know that boy is the hardest one to keep but will be very rewarding in the end with its beautiful colors. here's how mine was done, PBT was QT full 6 weeks in hypo along with desjardini then added to main display. two weeks later added orange shoulder, yellow tang and foxface, two more weeks added blue spotted kole and pair blue jaw triggers along with other small fishes in between. once when all the tangs was added they started to fight and sure enough ICH came back and covered the PBT for 2 whole months, all i did was mixed zoecon, selcon and garlic extreme to nori every other day for past 4 months along heavy feeding 3-4 daily did the job and PBT is now ICH free. before i panic and removed the fishes from display causing more stressed chasing after them so i left them in there and hope for the best.