Over the past 2 days 5-10 of these weird gray growths have popped up in my tank. All very small with a tiny stem and grey head. Have looked at some basic identification guides and can’t seem to find it. Tank is 2 month olds, 9.5DKH, 0 Nitrates, .01 Phosphate. Dry rock start with dipped corals. Any idea what this is? There seem to be growing at random places on my rock. can provide better pics and more details as needed. Referring to tiny grey dot under Zoa