The color red is one of the first colors to transition to brown, then black with the loss of light. Typically, the deeper the water, the less light. The same can be said for low light conditions, murky water or on windy days with wave action, which also cuts the ability of light to penetrate water. A red hook, lure, line or anything for that matter, will be black without enough light to refract a red. That being said, it would seem reasonable that on shallow running lures, using red might be a good option, but with lures that are deeper than, say 5 feet, the color red will transition to brown, the ultimately transition to black. Personally, I use red hooks on shallow running cranks or medium cranks in water that is gin clear, but I can't tell you if it catches me more fish. I just think it does. Laughing