Based on the popularity of the single hook Rainbow Trout I added it as a Tandem trolling fly as well. A number of years ago there was a study about planted rainbow trout. It was determined that as many as 40% of them were eaten by larger trout. This pattern is a good place to start on waters with planter rainbows if you are after browns or mackinaw. Fish the lake perimeter where you can see the bottom on one side of the boat and the gray-blue of deep water on the other. Predators lurk in deep water adjacent to the shallows where smaller trout are feeding on insects.