I purchased a tank that came with large numbers of Aptaisia
Commercial aptaisia products, lemon juice , kalwasser, boiling H2O will beat back the ones you get a direct hit on...a lot of time and effort and then they are back again...usually with a bunch more family members! The copperbanded I have doesn't seem to notice them, the peppermint shrimps made no difference and disappeared over time. Sprung's reference suggested a huge number of peppermint shrimp so perhaps the 6 I had wasn't adequate. Next I will try Berghia..who knows perhaps that will work. Fortunately, to date, the corals don't seem to mind the Aptasia as much as I do..they grow side by side among the zoas and are within the nooks and crannies of of the digi. However I would like them gone.