Ich Attack is another word for "snake oil". Tried it. Kept losing fish, lost (or nearly so - there's still a smidge of color there . . . ) a Blastomussa, ich laughed in my face.
Took out all my fish and treated with copper. (This worked, but not well for my wrasses...) Another week or so, and the DT will be ready to receive finned life again.
Hope that your fallow period goes well - and ends with a healthy, happy tank!
~Bruce