Need help IDing Dinos

[Jdgreef24]

I’m running a RSR350 for about 4 months now. 5 fish. No coral yet. Nutrients always come up very low but not zip. All of the sudden this bloom spreads all over the back wall and the normal brown on the rock that comes with the brown ugly phase starts hairing out in itty bitty tufts on the rock. See below for pictures. I’d really love some help IDing what’s happening so I can take the right action. Much appreciated!

 

[dwest]

I don’t think the tufts are dinos.

 

[Texas Rick]

Following, I have that issue too

 

[Jdgreef24]

I wish I had a filter clip so I can take a better picture. They’re spreading and are a little stringy. If you look incredibly closely you can see the tiniest little bubbles. So far I pulled back on the lights stopped 1 gallon auto water change and went back to strictly frozen mysis. ULR phosphate checker read at 2/.006

 

[Texas Rick]

I wish I had a filter clip so I can take a better picture. They’re spreading and are a little stringy. If you look incredibly closely you can see the tiniest little bubbles. So far I pulled back on the lights stopped 1 gallon auto water change and went back to strictly frozen mysis. ULR phosphate checker read at 2/.006

Yes, they do have really tiny bubbles. The bubble will get bigger then float away. Then start the process again. It may be some type of brown algae or so. But I’m not sure.