Your probably never gonna get rid of every single one, but some in the tank is not that big of a deal imo. The nudis seem to work really well but if you have a wrasse or another fish like it, it will eat them all before they can make any kind of dent in the Aiptasia. Aiptasia eating file fish will eat them up but now your adding a fish, potentially causing some quarrels with the new fish. If you get the correct peppermint shrimpd they will also eat the Aiptasia but like nudis any fish that can eat them will. I dont have either of those options so every month or so I dose them with Aiptasia x which works really well for me and keeps them in check. I would definitely not pull any live rocks with Aiptasia on them and nuke the rocks just to try and eradicate the Aiptasia as it will kill all the good things in/on the rocks which would probably cause problems in your system. Good luck and don't sweat Aiptasia's in your tank.