i recently got a colony of purple zoas also close for no particular reason , fresh water dip it also no improvement , yesterday did a furan 2 dip
all my other zoas colony is opening up fine, just this 1 , for the last 1 week , brown algae starting to grow on the polyps which i have wash off
no white film or pest , i just duno y it refuses to open , hopefully the furan 2 dip helps , will observe tonite