Without a man made physical environment people can not live underwater because we do not have gills like fish do. There are places in the world that have been made where you can live underwater for a short time. I think there is a hotel off the coast of Florida that is underwater.
On the sea floor
they live in the abyssal zone
Yes Eventually echinoderms do live in water.
Yes, they do.
Well fish poo does.
ocen floor
Most sea floor animals eat decaying food particles. This can be leftovers from what other sea animals that live higher up have eaten.
they live on the floor of the ocean . The ocean it lives on is the irish sea:0
On the ocean floor usually near rocky shore.
On the deep sea floor in temperate regions of the world
They like to live under rocks on the sea floor.
Starfish live in every ocean but the arctic ocean, they live on the sea floor and stick to rock and coral :)