Divad asked what what flies I fish when the water is high with poor visibility. For really murky conditions I fish 3-6 inch tube flies.. Here's the British Willie Gunn pattern that started the tube fly revolution. It's about 3-4 inches.
And my own bright 3 inch tube fly in steelhead colors.
Some big temple dog tubes. They are 3-5 inches
And some black tube flies 3-6 inches long. I like to dress them up with jungle cock and a little flash. I carry the patterns on copper, brass, aluminum and plastic tubes and vary the tube based on how deep I want to fish in the water.