Hey Scott,
If you are adding peppermint shrimp to your tank to clear up aiptasia, make sure you look up what real peppermint shrimp look like. Most "peppermint shrimp" aren't actually peppermint shrimp and often won't touch aiptasia.
There are many species that are lumped together under the genus aiptasia, hence you'll likely receive a lot of different opinions from hobbyists as to their effects in a reeftank (some consider them the worst pest and others believe the response to aiptasia is overblown- neither is right or wrong, it just depends on perspective and their particular experience).
Some are more aggressive than others and can harm fish, inverts, or coral. Some rapidly divide and can overtake a tank very quickly and are hard to eradicate faster than they reproduce. Others seem to be less aggressive and reproduce much slower. Some tanks are able to exist with aiptasia relatively peacefully, while other tanks can quickly be overrun. For many hobbyists who have encountered the more aggressive aiptasia species, they tend to eliminate all aiptasia on sight as it's easier to stop an infestation when the numbers are pretty small. Others adopt a wait and see approach and the last group of reefers tends to let everything settle out naturally.