I put three in.. have not seen them.. most likely expensive snacks..
Meh... i am having this problem too, because i got really lazy the past month due to being sick.
But i bought about 20 Behrugia... i purposely did not keep any wrasse because of this reason.
But even dropping that many, i have not seen a single one, and im still using aptasia X along with small water changes where i try to scrape / siphon what aptasia i see into a bucket.
As for file fish.. i have learned the hard way... NEVER and NEVER get an animal to take care of that problem, unless your at your last end, and your prepared to shift the problem somewhere else to something more managable.
Meaning while a filefish maybe a solution, it also introduces a WHOLE lot of other issues while taking care of that one issue you could not fix. (shifting problem from one to another)
So read up on all the uglies of file fishes, and well if he really ticks you off, they taste really good dried and then roasted over fire. :X
(this is a joke.. please dont roast a file fish as its poisonous, and needs special preparation like that korean snack)
That will give you some satisfaction after it eats your prized coral once its done with aptasia.