These little white strands are coming out of rock work especially in the evening they are all over the place. Tried suck and grabbing with tweezers and they just retract. I was doing some research and they look like digitate hydroids and doesn't seem as if there is anyway to rid of them completely. I haven't added anything new to tank in a couple months and everything gets dipped. Please help me ID and get rid of these things if possible!! I can give tank parameters if needed. It's about 7 months old and seeing first signs of Coraline algae starting. Noticed the critters start popping up about 3 weeks ago or so. Appreciate any thoughts or advice since im a fairly new to reefing.