Hey guys. I JUST took over my friends tank and have had the live rock in the tank after it has been moved from his house to mine with new water and a major clean up for about 3 days. He told me he had some pieces of coral in there but they were dead. Not sure if this is a piece of coral but I am pretty sure something is growing on it. They look like a hole bunch of little white hairs about 2 cm long and they sway around but I am pretty sure I have seen them get bigger in one day. Here is a pic if you look close. Hope it turns out well. Thanks