spotty flat algae?

Hi guys and gals,

Quick question I hope: if you look in this picture, on the very top rock there is this green kindof algae that seems flat and shows up like spots. What kind is it and should i be concerned? I just noticed that within the last week it has quickly grown on many other rocks in my tank and has grown overtop of the very little coraline that i have :-( I want more coraline, not this stuff, lol...what is it? Thanks! Michelle

Yep looks like algae. What kind of water do you use? Is it RODI only? Do you have enough water flow in there? What kind of food do you feed, how much and how often?

Yea I use RO water. I have lots of flow...i have a hang on filter and protein skimmer that produce flow, one 400 maxi jet aimed at the surface, and another power head on the opposite side and lover in the tank that rotates water. I feed frozen food every other day, sometimes every two days. My tank is still new, so i kno im battling some new tank syndrome stuff. I also have some red cyano on the sand but its not real bad and it comes and goes. I use phosphoguard and carbon every now and again too. Lights are PC's, one on for 6 hours, and one on for 4 hours.