Oftentimes fish or inverts that we get to solve a problem creates another.
As an example, I had peppermints to help with Aptasia. They did a great job, and then once the Aptasia were gone Acans were next on the menu... About $1000 worth... Filefish can decimate Zoas or LPS in short order if they don't have enough food I.e. Aptasia. If they eat other things besides the pest anemones, they may tend to ignore the Aptasia.
Kind of a fine line to walk. There will always be those who have had success, but there are many more who found out the hard way...