new fish QT time frame?

[e46er]

i have a foxface and a hippo tang in QT right now they had a week in the QT with 0.3 mg/L copper and a week at 0.5 mg/L both fish are swimming actively and no signs of any disease or parasites is a good enough amount of time?
what is the usual/standard time frame?
first fish ive ever QT'ed by the way after the ich outbreak 2 months ago im not making that mistake again