Why are my rocks so green?

[gdleader]

I've noticed that I am getting coraline on my rocks, but the rocks are very green and so is the sand. What am I doing wrong? I've noticed that most people's sand are white...mine were too but now turning green. I know it's sort of an alge, but how could I fix it. I will post pictures today once I get home. Thanks for any feedbacks!

 

[reefkprz]

its a phase it'll pass. (this is a very general answer) ther could be other factors but in newer tanks its really common to go through a bright green algae phase.