The benefits are obvious. Then, how can you explain origin of alternative view on anemone feeding (especially, expressed by a specialist)?
http://www.animalnetwork.com/fish2/aqfm/1997/aug/wb/default.asp: “The entire prey item should be fed. Avoid feeding just muscle tissue. Predators get important and essential nutrition from all parts of their prey, including the guts and internal organs. Stichodactyla haddoni, the “saddle carpet anemone,” eats whole fish and almost never regurgitates any remains, indicating total use of the food. Entacmaea quadricolor, on the other hand, appears to thrive on crustacean prey. Large whole krill, about the size of cocktail shrimp, fed regularly will lead to growth and a healthy appearance, and relatively little will be regurgitated here as well. Many anemones, including the Pacific host anemones, have zooxanthellae. People tend to believe that animals with zooxanthellae don’t need to be fed or fed very much. This is definitely not the case. Zooxanthellae may provide nutrition to a sea anemone, but the zooxanthellae, in turn, need many chemicals, such as nitrogenous compounds, available onl
