SUNLIGHT ZONE
This zone is where aquatic life is most abundant. It is where the maximum amount of sunlight reaches the water between 0 and 200 meters (656 feet) below the ocean’s surface. Traveling farther down into the sunlight zone puts more water overhead, meaning there is more pressure as the weight of the water starts pressing down. The deeper down into this zone, the less chance sunlight has to pass through the water.
TWILIGHT ZONE
For the human eye, this zone appears to be in almost complete darkness. Very little sunlight has the opportunity to penetrate this deep—as this zone reaches from 200 to 800 meters (656 to 2,625 feet) below the surface. Special diving suits are required for humans to reach this level, as the amount of underwater pressure in this zone could cause serious harm to the human body.
MIDNIGHT ZONE
As the name suggests, the Midnight Zone is covered in constant darkness—not even the brightest rays of the summer sun can penetrate the depths of 1,000 to 4,000 meters (3,281 to 13,123 feet). While there is not much life at this level of the ocean, there are a few creatures who call this dark and cold zone their home.
ZERO SUNLIGHT ZONE
This zone, also referred to as the Hadal Zone, is the deepest part of the ocean and reaches past the ocean floor and descends into the deepest ocean trenches. There is not much life in this bleak zone, however, scientists have found lobsters, crabs, and angler fish near the upper portion of this zone at around 6,000 meters (19,685 feet).