What is this white string on my frogspawn?

[Jakepen]

Woke up this morning, looked in my tank with a light and saw this. It's like a long string.

 

[reef lover]

That's a messentrial filament (spelling lol) they use them to destroy other corals when competing for space. And they will sometimes put them out if they're aggrevated.

 

[Jakepen]

That's a messentrial filament (spelling lol) they use them to destroy other corals when competing for space. And they will sometimes put them out if they're aggrevated.

Oh, did not know euphyllia had them as well. Maybe because my other ones are more full, I've never been able to see that before. This one is just a little guy.