what is this

[art]

I searched it on the net. It maybe the dinoflagellates. One thing tonight I watched as a snail did his best to avoid it. I have a few corals that are showing signs of stress. And I had tufa rock that I threw out because it was giving of something into the water. I will empty my tank tomorrow and start again. I have a large batch of diy rock that should be ready for the beginning of April. It is hard to see but there are long hair like structures that break of and float around the tank.