Baseball size handfull
Caulerpa racemosa is one of the most popular species for the aquarium hobby but several others can be regularly found. Caulerpa lentillifera is an especially attractive species typically grown for food in Asian countries but does just as well as an ornamental macroalgae.
Caulerpa macroalgae tend to be pale green with a soft, succulent texture that makes them palatable to animals and humans alike. All can reproduce by fragmentation; breaking them into pieces results in multiple new plants.
Small wonder they are invasive in many regions, including the Mediterranean. Sea Grapes can also get out of hand in aquariums unless herbivorous fish and invertebrates keep them in check.