Seaweed
"Seaweed" is a colloquial term and lacks a formal definition. A seaweed may belong to one of several groups of multicellular algae: the red algae, green algae, and brown algae. As these three groups do not have a common multicellular ancestor, the seaweed are in a polyphyletic group. In addition, some tuft-forming bluegreen algae (Cyanobacteria) are sometimes considered to be seaweed.
Seaweed cultivator
The type of seaweed that can be grown in a seaweed cultivator is currently limited to green types, mostly Angel Hair and sea lettuce, because other types such as Nori require more complex control of the water temperature and other variables. Angel Hair and sea lettuce, however, can be grown at home at room temperature.