HELP: Zoas have something bothering them

[RCode]

Hey all,

Been reading the board for a couple months just trying to learn as much as possible.

I found the last week my one frag of
zoas has been opening and closing when the lights are on, which isn't normal from when they were looking good.

After looking at them over and over I saw this inside them. What is it? And what is the best way to remove it?

Thanks!

 

[aguila88psi]

I'm thinking hydroid. I've seen them before and I just pluck them with tweezers, they came from a sunny d frag I got from a friend. They can reproduce quickly but for some reason they disappeared from my tank after a couple months, don't know why.

 

[A. Grandis]

Aiptasia?
Let them close and carefully scrape the thing side ways.
Rinse in tap water and return to the tank.

Grandis.