It gets dark & the pressure goes way up.
what happens is the ocean floor does not just keep spreading.instead, it sinks beneath deep underwater canyons called deep- ocean trenches
subdution
How deep can dolphins go
because of ocean trenches are so deep that man made water crafts can't go that low
Depending on depth of ocean, the diatoms size shrinks
Deep ocean trenches form
Well it normally depends on how deep in the ocean you go,
Deep ocean pressures are to great for submarines. They do not need to go deep anyway, just to avoid detection by the enemy.
It gets colder because the Sunlight heats the ocean and the deeper you go, the less penetrating the Sunlight is, therefore making the ocean water colder.
To the very deep ocean.
no
so deep you could see things