Orchid Pests - Phase II

Crap: the months of insect spray is not working. I repotted 2 of the catts and found significant amounts of scales on the roots still. Phase II - Bayer Flower & Rose Systemic Insecticide. Am repotting all the orchids, dunking them every couple weeks into the solution, and have every hope that they'll be eradicated. From my searchs, seem to be very successful for many others without damaging the orchids. Wonder how long it'll take me to repot 51 orchids, the ones on the rolling shelves. Really need to repot the cyms too, but 1 thing at a time.