There is no "usable" light agter 200 meters...
Sunlight can penetrate into the ocean to an average depth of about 200 meters (656 feet). This depth can vary depending on factors such as water clarity, time of day, and geographic location. Beyond this depth, the ocean becomes progressively darker as less sunlight is able to penetrate.
The upper 100 -200 m of the ocean is called the Photic zone (photo = light).At about 150 meters 99% of light is absorbed.Beyond the Photic zone, light does not penetrate, and it is pitch dark.
The depth light can penetrate underwater depends on water clarity and the angle of the sun. In clear ocean water, sunlight can penetrate up to 200 meters (656 feet). In murky or turbid water, light penetration may only be a few meters.
Ultraviolet (UV) light can penetrate water to a depth of about 1 meter in clear ocean water, but this depth decreases in more turbid or polluted water. Beyond this depth, the UV light is effectively absorbed by the water molecules. UV light is important in water as it helps to sterilize and cleanse the water by killing off bacteria and other microorganisms.
The average depth of the ocean is about 2.5 miles.
The average depth of the Indian ocean is I dont know honestly
The average depth of the Pacific Ocean is around 12,080 feet.
sound waves can penetrate the ocean floor.
they are absorbed
Red light does not penetrate to depths where red algae can carry out photosynthesis. This is why red algae have evolved to absorb blue and green light for photosynthesis at these depths.
Red light does not penetrate 70 meters beneath the ocean surface as it is quickly absorbed by water molecules.
The wavelengths of light that penetrate deepest into the ocean are blue and green light. These colors can travel the farthest through water because they are absorbed less by water molecules and particles.