Hi, I was using Typhoon a light sensitive strain grown a lot at lat 59. The iso was a anti-freeze for air conditioner in cars and bought from Shell. It just contents isopropyl alcohol, no additives. Washed for about 20-30s, filtered and purged lightly over a hot plate and left to cool over night. This just left a tar like substance that smells of petrol. I couldn´´t bring myself to use it, just too ugly and too smelly. Thanks for your interest though.