Feeding coral and manjos
Majanos are a type of anemone that are generally unwanted. If you feed your tank at all, they will get ahold of some food. Although not as quick as aptasia, they will spread rather quickly and can sting other corals.
You can try boiling RO water and injecting that in them, or kalk pasting them. Craigar just sold a "majano wand" to another club member. It appeared to use electricity to melt majanos.