the white curly stuff that the mushrooms are extruding are their acotina fillaments. if they are stressed at all or are possibly gettign stung, they expell these thigns as a defensive response. if you rub a mushroom with your finger after awhile you will see them doign this because they are stressed. most other corals can do this as well, i see it from time to time on my moon, and red brain coral. its a normal process and nothign to be worried about. good luck
jon