““At the ocean’s surface, the sun’s energy penetrates easily through the water. Deeper down, that energy fades until, at depths of around three thousand feet, there is no light. Longer-wavelength colors, like red and orange, are easiest for water molecules to absorb, and so they drop out first. The color red becomes invisible to the human eye at around fifty feet down; yellows disappear at around a hundred and fifty feet; greens at two hundred feet, and so on, ultimately leaving only stronger, shorter-wave colors like blue and purple. The””
