I have a Current Nova Extreme fixture with 4x54W High Output lights. I had Power compacts before and these lights are so much better it isn't funny. I would highly recommend T5 H.O.
I used "Purple Up" with good success when I started my tank, now the coraline is out of control. Try using Seachem Marine Buffer. The coraline won't grow with a low pH, that's one of the reasons you are getting Cyano. Hope this helps.