From the CO2Science archive: Gracilaria sp. is also called Irish moss. But we don’t know why since it comes from countries throughout South Asia, South America and Africa, yet not apparently from Ireland. Although apparently it is useful for clarifying beer during the brewing process so maybe that’s the connection. It is also useful for many purposes in food, cosmetic and medicine production. It is cultivated in the water but apparently it too benefits from extra CO2. In 1993 there was an experiment that showed an extra 600 ppm CO2 boosted its growth by 120% and an extra 900 million ppm boosted its growth by 137%.