Help with ID of Corals

[noirsphynx]

Anyone have any idea what this is. I purchased a blue sponge and it has two corals growing along either side of it(also a black soft thing along the back). One looks like maybe some kind of brain (but it also has some small tentacles all over) the other I'm not sure. They're both hard corals but the one on the left has some tiny holes in it and out pop these tiny "sweepers" It reminds me of the feather like maxillipeds on my Porcelin crab. I've added a pick of the sponge with the unidentified corals and one of each. I put red dots beside the openings where the "sweepers" are popping out to feed.