The green variation seems to be quite common in this area.
The wikipedia page which our taxa page links to suggests that their colour is dependant upon the amount of sunlight they receive, in which case I wouldn't expect to find red and green variations side by side.
Anemone eating a Spiny Brittle Star
Cnidaria (/naɪˈdɛəriə/ with a silent c) is a phylum containing over 10,000species of animals found exclusively in aquatic and mostly marine environments. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell thick. They have two basic body forms: swimming medusae and sessile polyps, both of which are radially symmetrical with mouths...