Question

hey there.

Answer 1

Algae requires photosynthesis. The deeper the water, the less light that can be photosynthesized, since it is diffused by the water. That is why the photic zone is called that... Photosynthesis can happen there, but any farther down. So things in shallower water can get light to photosynthesize, which algae need, but the things living in deeper water cannot photosynthesize, so there will not be algae, which requires light.

Answer 2

Confusing? I can right a shorter one...

Answer 3

wright*