Has the UV wiped them out yet? I think I have Coolia too. My nutrients bottomed out and stayed that way for months, which must've allowed the dinos to take over. They mainly grow on hair algae and seagrass.
Not yet.... With a mag 12 powering my 114w uv and a sicce 5 powering 57w my temps were climbing. I turned off the 114w until I got a new DC pump. During that time my sicce 5 died and I didn't notice. So two weeks with no uv and the dinos made a comback.
My nutrient levels as of yesterday:
P - .02
N - 2.
I've got the UVs back online and dosing N and P again