I've put peppermints in just glass tanks that had aptasia and if they get food from you or other sources, a majority of the time they seem to ignore the aptasia. Also others have noted that when peppermints do tackle aptasia, its only the smaller ones. You appear to have some fairly large ones.
use a small amount of lime/kalc mixed with a 2mls of water to make a slurry. then use a syringe and squirt the slurry on the atipasia head and voila in 10 minutes it is killed with fire.
I know I'm going to get rotten tomatoes thrown at me for this but I haven't decided whether or not to kill it yet. If the shrimp go for it so be it but I have no corals being affected right now and is not the ugliest thing in the world. Just kind of up in the air about it.
When they take off and your tank is covered in them it wont be fun then... just sayin... they spore pretty much nightly and when they get going they are hard to eradicate. i know someone who thought they were neat... until they had around 300 strong....
If you don't kill them or get rid of them somehow they will eventually overrun the tank. They will kill corals and take away places that your fish like to hide / sleep thus stressing the fish...I just went through this with a 90G.
i count at least 7 in your pic with the peppermint shrimp.. there is a type of nudibranch that eats it as well... you have a full blown invasion beginning it looks like.