Looks like cyano, aptasia are very hard to get rid of if left unmitigated for even a short period of time. You can try kalk paste, aptasiaX, or a mojano wand. The only other options involve removing the rock all together. In my experience killing them in any fashion within the tank results in 2-3x more popping up elsewhere. Aptasia are a royal pain to deal with, the best end-all solution is to find something that will eat them, though after the aptasia is all gone it will ultimatly starve if its an aptasia eatting machine. You could always get a aptasia eatting filefish if it gets bad enough and return it to the store once your confident they are all gone.