Chironomids can be fished under an indicator or without an indicator and a long leader (5-30ft) from a floating line. You can also fish them vertically using a full sinking line that you retrieve incredibly slowly. Pupae rise up from the bottom of a lake and emerge at the surface as an adult midge. Fish like them. Lots of sizes and colors to imitate.
Weight: some folks use a tungsten bead, others add a swivel or split shot to the leader
The real thing: