Common Name: Cactus algae , Halimeda.
Scientific Name: Halimeda Incrassata.
Very similar to another cactus algea, Halimeda Opuntia, in size and form. Mature plants can grow as tall as 20 cm or so, but most will stay small in an aquarium. It grows exclusively in substrate and needs a deep sand bed of 10 cm or more. It can grow very quick, 3 cm a day. Not palatable to fish or invertebrates.
Common Opinion: GOOD