Of all colors of the spectrum, red disappears first when in water. Though the color is gone, the object still exsists. So fish do, in fact, see it. A proper understanding of how fish see is required.
From a distance, the red will appear as a shade of grey. Black hooks retain their dark properties. Natural metal will appear as a grey while shiny hooks produce the shimmer of something shiny. As the fish enters the color field, the colors do become apparent.
Here is something for y'all to consider. Imagine a triangle with a straight line drawn from the top peak to the bottom center. This line represents point of origin for each color. At the top is red, then orange, yellow, green, blue and violet is found at the bottom. Inside this triangle, you can see where red covers the smallest of distance before disappearing, orange is next the yellow.... violet being the color that travels the greatest distance from the point of origin. This is how color dissipates as it leaves its source { that center line from top peak to bottom center}.
As expected, the way fish see things depend largely on depth, water clarity, patterns of objects, coloration, and the species of the fish in that general area. Eye design between the various species is just as varid as the species. Some fish have more cones than rods while others will possess more rods than cones and some have equal or nearly equal of each.
Cones allow the fish to see colors while rods give the ability to see in various light conditions. More rods equals better dark enviroment sight. This is why many species are attracted to light- it gives those with fewer rods the ability to see what they normally would not.
Because the eyes are on the sides of the head, most sighted objects will appear in 2D. If the fish moves its head from side to side, the brain in most fish can reprocess the image to 3D. Oddly enough, this 3D vision allows the fish to hone better, making a sucessful strike and we perceive the frequently caught fish as "dumb" because they fall for the bait so often. The truth is they are better able to process depth perception than fish with limited {life saving} 2D.
In the end, the hook color really makes no outstanding difference as, again, the fish must enter the color field to strike the lure/bait. You have to rely more on the targeted species sight capabilities and exploit that when choosing your gear. Those that chart when, where, time and tide info on catch rates and failures are tracking what works without realizing they are actually doing biological studies. Each variance in lure color in relation to water conditions and species and sucess/failure rate is what makes or breaks a day on the water so be sure to record details and gather as many details as you can from others.
That red hook may work great for one species but not for another.