what kind of anemone are these?

[JakartaOrBust]

My brothers tank has a large colony of Majanos, his clowns use them as a surrogate. But when some of them multiply or grow towards other corals, we use a syringe with pure lemon juice. It shows no affect to any of the other animals in his reef. If you don't like the home remedies, joes juice should do the trick.