F. implexa are famous for forming large three dimensional colonies which encrust rocky substratum and often exist epizoically with many living organisms on reef such as bryozoans, corals and the shell of a range of molluscs (Glasby, 2000).  Furthermore, they are also able to occupy the sandy habitat of the lower shoreline and the sublittorial zone (Richards, 2008).  Studies have demonstrated that species is particularly abundant at undisturbed deep water sites (of 33 - 55m) where they attach to pebbles on the ocean floor in comparison to the rocky crevices and shell interiors which they are commonly found in shallower waters (Collie, 2000).

Sandy substrate habitat with rocky crevices for filograna implexa settlement
Photo by Tanya Pernase