Whats up with the Zoas

[Tron_954]

Any clues as to why they curl their skirts a little bit and don't fully open?

20140807_141152 by J.L Photography, on Flickr

 

[Mael]

looks like something may be irritating them, mine do that occasionally when a fish brushes against it or a one of the stoma snails crals on it.

Other thing to look for is the tiny tube worms putting out their filaments, technically it doesnt hurt the zoas but it does irritate them.