0 to break up nitrates (= chemicals containing nitrogen and oxygen), for example in soil, and so release nitrogen into the air: --
1 to remove nitrogen (= one of the gases that surrounds the earth) or chemicals containing nitrogen, for example, from the soil (= material on the surface of the ground), and so release it into the air --
Some organisms appear to be able to denitrify and remove phosphorus.
Hobbyist aquaria often do not have sufficient bacteria populations to adequately denitrify waste.
Water can be denitrified by the use of bacteria, but that cannot be done on a large scale.
