Upside down polyp

[Pezking182]

I have these zoas and 1 polyp is open but looks like an umbrella (the one at the top). All the rest are fine. Theyre growing quick as well.

Tank water
Sg 1.026
Cal 450
Dkh 8.4
Mag 1600
Temp 78.5
Nitrates 20ppm

I also noticed that this one particular polyp doesnt close up at night like rest.

Any ideas?
Thanks

View attachment 20180829_194915.jpg

 

[Crabs McJones]

Looks like zoanthid umbrella syndrom. Usually caused by lighting changes or parameter changes or something the zoanthid doesnt like. Weird that only one is doing it. They tend to go back to normal on their own.

 

[Capitol Reef Corals]

I wouldn't worry too much about it. Monitor it, but it usually goes back to normal within a few days.