algae

[BigT]

hi new to the hobby. Started my tank May 17, Its a 65 gallon tank with a sump, 75 pounds of live rock with two coral life metal halide clamp on lights. Last friday started noticing a little bit of algae growing, today tuesday most of my live rock with exposed surfaces seem to have a green fuzzy algae on it. Is this a big problem and if so how can I correct it so my tank isn't overrun by the time I add any fish/inverts/corals.

Thanks