It may also be diatoms, and not cyanobacteria. Cyano tends to be a dark red (though it can look brownish at times) and grows in a sort of mat. If it looks like a brown dusting (though it may be a very thick dusting if you have a bad case), it's probably diatoms. If it looks like something inbetween often with air bubbles forming in it, it could be dinoflagellates. I believe Chemiclean is only effective against cyanobacteria, but there can be side effects, and I agree with turretdr 100% that it's not the best solution.
Your tank is still pretty new, so an algae breakout is not at all uncommon. The best prevention/pure is regular water changes, using only purified water (RO/DI is preferred), not overfeeding your fish, and practicing overall good tank husbandry. GFO phosphate removers are often helpful, as they remove phosphates that are often the biggest contributer to algae growth. It's not going to go away overnight, though, so you have to be patient.
Lastly, if you post a picture, we should be able to identify the algae.
