If you have room, get two. Two average skimmers will pull more than one super-awesome one. They often cost less too. Few people do this, but it is a really good way to go. I used to use a ER 12-2 and a huge MRC beckett with a panworld 120 when I had a bigger tanks. Now I run that same ER 12-2 and a Octopus with a 8" body and Sicce pump (which I am amazed at how good it really is) - neither of these will outskim a BK on their own, but they crush a BK together.