Hi @idrisIn terms of getting back to usual, is it now worth staying off the Carbon and running a reduced photo-period for a week or so?
Let's wait until tomorrow when you can give us an update on your tank. If the Blue Exit has been effective, the Cyano should be starting to blacken. We can possibly increase the dose of Blue Exit depending on how effective it's been. When you refer to 'Carbon', is this a liquid carbon fertilizer? If so, it may interfere with the effectiveness of Blue Exit. Possibly more important than reducing the photoperiod would be to reduce the lighting intensity (brightness). Or, you could combine both.
JPC