I tie and fish midges in the lakes around here, and have had my best luck with blood midge emergers. I cast them out, let the set for a while, and then very slowly, twist retrieve them in. I don't fish midges a lot in the river, mostly streamers and nymphs there. My most effective midge has been a martis midge in orange or red. I am not the expert on midges, but that is my experience. Hopefully Joni or Mojo will chime in as I believe they fish a lot of midges and chironimids. I think Macnerney also fishes midges, and he can probably provide some good insight as well.
Hey mac, looks like you beat me to this one