Plant. Drifter. The ocean’s first food.

A way of life, not a family

Phytoplankton is a job description, not a branch of the tree of life. The word comes from the Greek phyto, meaning plant, and plankton, meaning drifter. A phytoplankton organism is anything that lives suspended in the water, photosynthesizes, and is too small to swim against a current. Biologists contrast the plankton with the nekton, the swimmers, such as fish, squid and whales, which can go where they want regardless of the current. If you drift and you photosynthesize, you are phytoplankton.

Because the category is about how an organism lives rather than what it is related to, it covers a huge range of unrelated life: diatoms, dinoflagellates, coccolithophores, green algae and eustigmatophytes all qualify. They are about as closely related to one another as bats, birds and bees, three groups that all fly without sharing a recent common ancestor for flight.

“Marine phytoplankton” on a label tells you how the organism lives and nothing about which organism it is.

Two products can both say marine phytoplankton while containing organisms from entirely different branches of life, with entirely different chemistry. Strain identity is what actually matters, and it is the first question to ask about any product in this space. LiveMineral answers it on the front of the box.

The strain in the box

LiveMineral is Microchloropsis gaditana. It belongs to the eustigmatophytes, one of the less familiar algal groups, and it is a genuine open-water phytoplankton organism that is also cultivated for product. Until 2015 it was known as Nannochloropsis gaditana, when Fawley and colleagues moved it into the new genus Microchloropsis (1). Both names appear throughout the published literature, and most of the older research is filed under the old one.

The base of the ocean’s food chain

Phytoplankton are the base nutrition of the ocean. Recent reviews describe them as providing an estimated half of global primary production (2, 3), which is the conversion of sunlight, water and carbon dioxide into living matter. Everything above them in the food chain eats, directly or indirectly, what they make.

That includes the omega-3s people associate with fish. Fish do not make their own EPA and DHA: they accumulate them by eating microalgae and the animals that eat microalgae. Reviews in 2025 and 2026 describe marine microalgae as the richest natural source of these fatty acids and a sustainable alternative to conventional seafood sources (4, 5).

Why cultivated matters

Phytoplankton in the open ocean is a mixed community, and the water it lives in carries whatever else is in the water. Cultivation does two things: it lets a producer grow one known strain on purpose, and it means nothing is taken out of the sea to make the product. LiveMineral is sustainably cultivated in Spain and processed in the USA. It is not harvested from the ocean.