Phytoplankton will engage in chemical warfare in crowded conditions to eliminate competing species.

Phyto2 Phytoplankton is a pure species of plankton suspended in purified sterile seawater.

In order appreciate what this means we must first understand how Phytoplankton competes in the ocean. When Phytoplankton encounters other species of Phytoplankton, it reacts by releasing poisons to kill the other species which in turn kills itself. When you concentrate and combine different species of Phytoplankton in a closed container it competes and at some point poisons the bottle, not only limiting shelf life but reducing nutritional value.