The name “Sea Lettuce” is a clue to both the appearance and the edibility of this species. This is a widely available type of macroalgae and is one of the hardiest species. Being very soft and delicious to most vegetarians, Sea Lettuce seems like a plant destined to fail.
However, Sea Lettuce grows in the intertidal zone where the land meets the ocean. Growing here, on wave swept rocks and gravel, it will be exposed to harsh light and hot air for hours at a time.
While relatively few organisms can survive here, the extreme temperature and salinity swings are just another day for Sea Lettuce. It also grows quickly enough to outpace snails, limpets, and other intertidal herbivores.
Being a favorite algae choice for most plant eaters, Sea Lettuce is best grown in a refugium or an aquarium with no herbivorous animals. It also prefers more current than most types of macroalgae.