What would have been working in February and March if it wasn't for the ice, are still the best offerings this year in early April. There were a few feeds near the surface before the rain raised the water levels - probably taking a stone, BWO, or black midge a few inches under. I still like a Slate Drake as a strike indicator with a double-bead Yellow Stone #14 on three feet of 4X tippet tied to the bend of the hook. Under that, and again tied to the bend of the stone I like a Micro Stone - also in a #14. Instead of the Yellow Stone you could use black, and for the Micro Stone you could substitute a Prince or Copper John. I also like tying two feet of 5X to my tippet ring above the Slate Drake with a Rhycophila in a #16 on the business end (the Rhycophila is unweighted and this rig allows it to maneuver under the surface much as a washed-away natural). To keep from tangling this rig, only make one backcast  to reposition your flies to the current. This set-up works!