Also known as giant kelp or giant sargassum. Translucent yellow-brown algae. It grows like a tree, from the ground to the surface and continues to grow, its branches grow from the bottom up and consist of a float for each frond, these filled with CO2, which keeps it moving towards the surface. Highly mucilaginous, with a lot of alginate; this helps it to re-hydrate or come into contact with any wet surface, it quickly regains its shape and texture, providing traces of its properties on whatever it touches.