Depends on species and physiology. A closed bladder fish (one with a swim bladder to compensate for buoyancy that is closed and very slow to exchange gasses) is limited in how quickly it can move vertically (up and down) and is therefore mostly limited in its depth range. However, other fish have open bladders and are much freer to swim up and down. Some species are found on the bottom in the deepest parts of the ocean and may have no bladder. Basically, fish are found in every depth of the ocean, so the easy answer is that it is all depths.
The maximum depth of the Caribbean Sea is 25,197 feet.
The maximum depth of the sea is 3,785 metres (12,418 ft).
Its maximum depth is 2,300 feet.
The average depth is 55 meters
Its average depth is only 44 meters (144 ft), with a maximum of 152 meters (500ft). The depth is gradually increasing from north to south.
The maximum depth of the Celtic Sea is approximately 2,000 meters (about 6,600 feet). This depth is found in the deeper areas of the sea, particularly near the continental shelf edges. The Celtic Sea is located between the southern coast of Ireland and the northern coast of France, and it plays a significant role in marine biodiversity and fishing.
The maximum pH occurs closer to the bottom of the sea than to the surface, in most cases.
the maximum depth of lake ontario is 244m or 803ft
The maximum depth of oceans is 10,923 meters/6,787 mi.
about 1300 miles up and down and 2100 kms
The Adlantic OceanThe adlantic is the shallowest as well as the smallest of the worlds oceans. Arctic Ocean's average depth is only one quarter that of the Pacific. Average depth: 3,407 feet (1,038 m)Deepest point: 17,881 feet (5,450 m) in the Eurasian Basin
The maximum depth of river Kaveri is about 217 ft deep