I am trying to identify marine growth species from still images as part of a university research project.
I am fairly sure that the bright orange and yellow organism is a species of Tubastrea. I am trying to identify the grey/white large round organisms. I believe it could be one of two options. 1) The shape and size is similar to the Tubastrea and I feel that it is possible that the once living coral may have bleached and died turning the colour and allowing for overgrowth. The external nature of the organism is calcerous and pieces flake of when probed. Some of the individual organisms flex in the current and when probed a indentation can be seen much like if you were to push a finger into a cushion.
The second option 2) Is that it could be a form of calcerous sponge, I know they can reach massive forms and shapes but I am not sure they would allow growth to occur over the top of them.
The location is West Africa (Gulf of Guinea) the distance from the coast is around 20km and as you may be able to tell its a oil and gas structure that the growth is on.