Hyposalinity question

I am in the process of curing my Copperbanded Butterfly and my Lemon Peel Mimic Tang of Ich by administering the Hyposalinity treatment but it is my first time doing so. They are both sitting in my 20g high QT which is bare of course with the exception of a fake aquarium log with fake plant in it to hide in and behind my salinity lvl is at 1.008 and my temp is at aroun 79 degrees F and Im constantly checking my PH to make sure its stays where it should be using a PH and alk buffer to raise it when I need to. My question is to anyone who has experience in this treatment is how long does it normally take before you can see some of the spots disappear and overall how long does this treatment normally take. I know what ever you tell me is not an exact and doesnt apply to every case but it at least gives me a time frame to look forward to.