Usually people add a handful of peps, but even then it's iffy, and then if they pick at things they are tougher to catch.
berghia nudibranchs and matted file fish are other options, both easier to catch if you want to pull them after.
Sometimes hitting apt w/ aptasia X melts them enough to make it easy for eating and encourages the eating of your aptasia.
The combo has worked for me, I have a CBB that took care of my aptasia, but they are a little trickier to keep.
I did not care for peps, they stole food and messed w/ snails.