Here's what I have done in the past. These are outside. It's a bit of overkill being that my blend of B70 is fine into the teens with barely a hint of it beginning to form a haze. As far as DK, I don't know how well it will work as designed in higher biodiesel blends. If I remember correctly, the bottle states it will work in blends of B20 or less. (BTW, that's B100 of the same batch on the far right)