Eucheuma, commonly known as sea moss or gusô (/ɡuˈsɔːʔ/), is a rhodophyte seaweed that may vary in color (purple, brown, and green).

"[9] Eucheuma are naturally found within the range of 20 degrees either side of the Equator in the Indo-Pacific region from eastern Africa to Guam, and are most concentrated in Southeast Asia.

[1] As a commercial crop, Eucheuma has since been distributed to many regions away from their original natural habitats, including Japan, Hawaii, and island nations in the South Pacific.

[citation needed] Once harvested, the product can be dried, packaged, and then transported to areas ready for carrageenan extraction or used as a food supply.

As Eucheuma is commercially important for economic growth, average annual production of total dried seaweeds, including other groups of sea plants, reached nearly 125,000 tonnes in the Philippines alone, by 2000–2004, with a value of approximately $US139 million.

[2] Once seed stocks have been obtained from the wild, they undergo cleaning in order to rid them of dirt and other contaminants, where they are then transferred to nursery sites in styrofoam boxes with air holes in the top, without exposure to the wind or the sun.

[2] Site selection is important in developing potential seaweed farms, and certain criteria must be met first in order to optimize production.

These criteria include suitable current and wave actions to allow for absorption of nutrients, sufficient but not excessive light to allow for optimum photosynthesis, a sufficient water depth not hindered by low tide exposure, an optimum water temperature between 27 and 30 degrees Celsius, salinity levels of 30–35 0/00, and areas with little presence of grazers, microorganisms, suspended silt, and epiphytes.