It's not that bad of a case. More than likely, it will go away partly on its own - it's a natural algae cycle in your tank - conditions for the cyano exist, it blooms, uses up its nutrients, and then dies off to a (usually unnoticeable) small amount where the nutrients/algae are in equilibrium. Not disagreeing with the advice above at all, but I just wouldn't lose my mind trying to instantly solve that algae problem in such a new tank...
I don't run a sump (Even though I think it would be helpful and I will have one on my 150) or any reactors and my tank (besides my light induced dino outbreak a few months ago) has no reactor....and I feed fairly heavily. I swear by the refugium I have, where I have lots of macroalgae. All my algae problems dropped off when I put that in.
I haven't been around the block too long, but that's just my experience....:twocents: