Cyano..
Welcome to a new tank.. Its fairly normal and can/will pass on its own..
Personally I let it happen (and just siphon it when I can and wait it out) because its natures way of helping the maturing process along IMO..
Its just another one of the "uglies" stages.. Diatoms first, then green algae, then cyano..
You can siphon it out with water changes,etc... black outs, chemiclean/red slime remover,etc...