I'm going to be getting a lovely Viking gas range with about 15,000 BTUs per burner. It's a 30" range, so theres 4 elements. We had the Ventahood all picked out as a range hood, but unfortunately we can't install it since our ducting is only 6", and the Ventahood requires a 6". The smaller 6" Ventahood is only 300cfm, and I was told that it's not enough for my range. I need some help getting a good range hood that would be adequate for my range, with only a 6" duct!