Alas not so poor cyano we knew you well.
Lights full on cycle today and no cyano left. Skimmer is a mess but wow 3 days of darkness worked like a charm.
There is so much gunk in the skimmer it is unbelievable that so much could have come from the water.
Thanks Reefing Madness for the suggestion. Worked like a charm.
Only downside, apart from the messy skimmer, is I cannot find one of my anemones, not sure if it gone or just hidden very well somewhere.
Slight issue with algae on the glass but can sort that tomorrow on water change Wednesday.
Coraline is growing nicely now as well on the powerheads, nice shade of purple on one and more appearing on my formally dead rock