Mine didn't eat aiptasia. You have to make sure you get Lysmata Wurdemanni not Lysmata Californica. I suspect the latter is what I had.

mine are great little community shrimp, never had an issue with them.

I'm close to swearing by them, but not quite there yet. I used to have bad aiptasia. Got some P'mints and also zapped with Joe's. Aiptasia on right side of tank was under control. Aiptasia on left side of tank became rampant again. Had a Coral Banded Shrimp on left side. They are known to prey on P'mints. Thus, I believe I did not have P'mints on left side. CBS probably ate them. Removed CBS to sump. Removed all LR from left side and scrubbed. Returned LR and added 7 new P'mints. This is going back about two months now. Some aiptasia I missed during the scrub reappeared. (P'mints won't eat big ones). Continued Joe Juicing the big ones. Slowly winning the battle. I'm planning on getting more P'mints. Have a nice big Frogspawn on left side that is thriving. I want to establish an army of P'mints. Maybe 30 or so. Right now I have about 10. Tank is a 180.
The experiment continues.

Cheers,

I had a pair they seemed to keep aiptasia under control still had to joes juice some, but then they started attacking my xenia's.