ID on green algae

[russelljew]

I have some green algae on a couple of live rock. I know its not hair algae, Im just getting over that and its not starting like it did. Its not bubbles in the pic, its sand that got blown up on it. It comes off easy. I sucked it off in a baster and now its back in couple of days.

 

[nikesb]

if its slimey, its green cyano but it doesnt look like it. its also coming off easy, so its not green coralline, so i'd bet on green cyano

 

[nycbob]

probably cyano. could be a sign of nutrient buildup.

 

[russelljew]

Two mornings in a row, Its almost gone. Then the lights come on its back getting darker than before.