how to get rid of aptasia(?)

[Edmonton newbie]

lol i had filefish in both my tanks full of zoas too now i have 2 tanks and i think i still have a single zoa head left, both filefish eat like pigs but everytime i turn around they hit the zoa gardens. i moved a small green tip from one tank to the other and looked back an hour later...... file fish with HUGE white lips and little bubble tip gone. my next tank will not have a filefish id rather take my chances with an angel