I am another Cyano fighter. Instant Ocean standard (non RC). Been having issues on and off, mostly on, since November.
125gallon reef tank, 20 gal sump
lots of LR
I feed mysis/coral frenzy/cyclopeeze every other day, 10 fish (3 clowns, 4 PJ cardinals, 1 chromis, 2 wrasses)
I top off daily...