Here are the figures I was given years ago on dilutions. A 10% final mixture is good to 25, a 20% good to 10, a 30% is good to 0 and a 40% is good to -10. I mix my methenol up by taking 5 to 10 gallons of methenol out of the barrel and adding 5 gallons of foamy brush concentrate. I go through a...