As it's already been said. Chemically, you can get rid of the stuff over night with Chemi-Clean, but if you can't control your nutrients, than it will come back stronger and more resilient to Chemi-Clean than before.
If you really want to make sure to get rid of it, just let it grow. It will eventually use its nutrients and die away as long as you don't keep feeding it. So, keep good practices on water changes, watch your bioload, watch how much you feed, and be patient. It will take up to a few months to get rid of it. On a good note, high flow helps deter the Cyanobacteria from settling down and growing in mats. FWIW, Cyanobacteria doesn't typically do any direct harm, so as long as you can keep it from growing on anything that needs light, it won't hurt anything.