Phytoplankton feed on the nutrients brought up by this type of deep cold water current

A water column is a form of precipitation which brings nutrients like nitrogen, carbon dioxide, iron and phosphorus. As phytoplankton create their own food source throw photosynthesis by converting sunlight into energy, a better word than feed on the nutrients, is absorb, as they do not gain energy from the nutrients, but the necessary nutrients allow for the phytoplankton to photosynthesize.