Just an FYI, in case you wish to search for info on the 'net.
It is properly "manjano", rather than "majano", and info using either rendition can be found:
Anemonia manjano Carlgren 1900.
Oscar Carlgren must have been thinking of turmeric (Swahili word = "manjano") when he named the anemone he first described from East Africa. Turmeric comes from a ginger plant (Curcuma longa)whose root is dried and ground into the yellow spice so richly included in the making of curry, and the clustered flower buds each resemble the shape of the anemone's partly-swollen tentacles.
Just didn't want you to miss out on some links
As for how to kill it, I dont use a 'kalk slurry', I don well-rinsed gloves, then with just a little water I make a kalk-paste pellet just big enough to bury the manjano anemone with. Suitably brutal and less prone to dilution like a slurry is.