green moss-like growth

[hessfish125]

Ok, my inexperience is showing big time. I have green moss-like stuff growing on my reef rock.

Is this a problem? How do I control it or remove it?

Also, how does it form so I can stop it from coming back?

[hessfish125]

any thoughts on what this is or how to eradicate it?

[JustinFromAL]

It looks like green turf algae, or the start of hair algae. Check here for an ID and more information -> http://www.reefcleaners.org/index.php?option=com_content&view=article&id=54&Itemid=60

As for the cause, it could be a lot of things. Phosphates are the most likely issue but it could be overfeeding, lighting, non 0 TDS water, etc.