Gotta love the aiptasia posts, LOL.
Peppermint shrimp WILL eat them as long as you have the correct ones. Lysmata Wurdemani, have well defined horizontal and vertical stripes. Lysmata Rathbunae look like L W, BUT THEY HAVE BLACK TAILS!! The end of the tail is black that is. The Rathbunae, you will be lucky if you EVER see touch an aiptasia.
What squirting the things with chemicals does, is not the chemicals fault. Once again, LOL, (just messin around), aiptasia form what I believe are called PETALS at the base of them. You squirt the aiptasia and it covers up the petals so they fly off later and create 14 more. But the aiptasia does die that you originally squirted.
Copperbands shouldn't even be brought into captivity. If you are one of the people that made it past the 25% success rate, congrats. But these fish are just way to delicate. I rank them up there with sweetlips.