filefish for apistatia control

[albano]

I have one of those file fish and he eats all the food I put in there and I havnt seen him eat an aptasia yet...

As Randy mentioned...you will rarely see them eat the aptasia...but it should 'disappear'.
When you say, that you 'have one of those file fish'...are you sure of the species? There are similar 'looking' file fish, that do not seem to ever eat aptasia...maybe post a pic of yours

 

[lfsmarineguy]

I will concur with the stealthy eradication. I have never seen one actually eat an aiptasia either but there will come a day when you notice their numbers start to dwindle. I never really thought about it but that's a funny point. You will see them eat the foods you offer though.