I had conquered it a few months go, was running a pmdd system, all was great, free of it for 6 months, then it appeared again, checks showed phosphate up to 5+.
I put in Rowaphose, done ,loads water changes and continuing to do so. Phosphate falling to about 2 now. Nitrate has always been at around 40. So I blame my poor tank maintenance for the outbreak, just though some chemi clean would speed things up..