Best advice I can give is don't add any media or additive that you are not testing for! I'd pull the chemipure and any carbon you are running (If any) until you get your nitrates and phosphates detectable.
As far as the algae and cyano, manual removal of both and give it time. Your system will stabilize and all will be good!
As far as the algae and cyano, manual removal of both and give it time. Your system will stabilize and all will be good!