Algae ID?

[RobbieMaynard]

Hello - My tank has just shy of 3 months old. The last couple of weeks I am starting to get this type of green algae blotches on my rocks. Anyone know what kind this is? Many thanks!

 

[Dan_P]

Would you rephotograph under white light? Color including shape help ID algae

 

[RobbieMaynard]

Sure. Here you go. Thanks in advance

 

[Dan_P]

Sure. Here you go. Thanks in advance

The overall greenish coloration may be a micro algae. The near circular colonies are not in focus when I enlarge them. I can’t see the structure, e.g., is it filamentous. The odd thing to me is its low form. Is it green hair algae that was mowed down by a snail. Sorry, that’s my best guess.

 

[RobbieMaynard]

I’ll take another pick tomorrow when the lights are on. Also I started with Marco rock. Nitrates reading 5ppms and phos: .11ppm