Ryz... it will only work for aiptasias that are easily accessible. Do it wrongly and you may even find a new aiptasia in its place if it wasn't completedly killed.
I gave up using kalkwasser paste because there are so many places in my LR that I can't reach... and leaving them there will guarantee a multiplication of plague proportions.
Even Copperbands may not even reach an aiptasia if it's in a awkward area.
From my experience with peppermints.... I give them two thumbs up! Every single aiptasia, in nooks and crannies, on clam shells... were cleaned up within the space of 1 month.
I have 4 peppermints and I see one of them with eggs... so it'll be even better coz I get natural and free coral and fish food!
Peppermint shrimps are reefsafe and I have never seen them disturb any zoos or other softies like xenias in my tank. They scavenge the sandbed and pick at stuff on my glass.