I can't believe how much bad advice you have given on such a small simple thread! Almost everything you have said is wrong or bad advice.
"With Caution" means NOT reef safe!!! And for the record, I have seen 10 times more non reef safe dwarf angels than reef safe dwarf angels, so its not 50/50 its like 90/10, at best.
Peppermint shrimp do not eat Majano Anemones they eat Aiptasia, and if it was Aiptasia, the peppermints might go after some of his corals, and you NEVER asked what coral he has (this applies to the filefish as well, as does tank size!).
People on here need to stop giving advice when they do not know what they are talking about.
To the OP.
You can not just shoot lemon juice on the anemone in question. You must get the lemon juice into the anemone, if I remember correctly.