Many fisherman swear by the zebra midge. I'm amazed that such a tiny fly will keep a fish on the end of your line even in fast water.
For a long time, I never caught anything on a zebra midge. But I was always fishing it off the back of a dry fly.
Tying tiny flies on tiny tippet in the cold...
Attach the zebra midge to the hook bend of a heavier nymph like a size 16-18 Rainbow warrior (with a tungsten bead). The dropper can be 8 inches to as much as 20 inches long.
Use a longer dropper if the fish are getting foul hooked by the upper fly.
Tightline Productions on Vimeo has a great tying video for the Zebra Midge