Do try the 7X and for what it's worth I use a 17''ft leader. Do I think everone should use a 17''? No, but it works for me. I do think you need a little longer leader. See whats best for you. I feel I can use 6X with a longer leader. I use 5X during the sulpher hatch and very seldom Do i think I need 6X. The smaller flies are a different story.The longer leader means you dont have as much fly line on the water causing less drag. IMO. Again theres tons of bugs during a midge hatch. So keep @ it. Hope this helps some.