Everything eats nudis. Peppermints, all wrasses that don't hide at night, copperbands, hawkfish, sally lightfoot crabs, etc.
At $10 a pop and when 1 nudi eats about 1x aiptasia a week, chances are it'll get eaten before they can make a dent if you have any of these inhabitants.
Island Fish and Scale is acclimating their copperbands and I personally know someones who started eating aiptasia within the 1st week brought home. Maybe get on their list