I’ve only had these Zoas for about two weeks I’d say and I noticed two days ago that there is a hair-like thing growing out of two of them. We bought 3 frags and only 2 are affected. The two affected are right by each other (view video) and the other frag is on the opposite side of the tank. I have a 75 gallon tank using the Fluval Sealight light. What is this and should I be concerned? (This is my first reef tank so I’m not the most experienced!)