Quote Originally Posted by dmagerl
When staring at the "fungus" do you see any kind of movement at all?

That sure looks like rotifers or vorticella on the plants. They attach to plants with springy stems and when disturbed will pull themselves downward. You should see them bouncing up and down. But I've never seen them take over an entire tank like that.

A magnifying glass will help.
The fungus appears completely immobile, really.

Also, I lack a magnifying glass or microscope so I can't get a close-up look. But looking at the shapes of vorticella and rotifers via the magic of Google image search, I can tell you that from what I can see doesn't fit the look of either and appears a lot more like bryozoans. Rather like this instead of this or this. The... flagellae, I guess, are much longer and appear pretty brush-like. Whatever they are, they're dying back what with the major upset in the tank, and their presence far preceded that of the "fungus".