hammer coral and high salinity in my tank

[tncoe18]

I notice everytime my tank is high in salinity (yes, I'm lazy and I don't check salinity dailiy like I was supposed to), my hammer coral would react in a very weird way:
It first shrink, but not completly, then there is this yellow string comes off the middle part of the coral. Can anyone explain this phenomenon and I was just wondering if my lovely hammer is in any kind of danger?

Thanks!

 

[melosu58]

If your salinity is bouncing around then it very much could be in danger. Corals need stability more than anything. Depending on size of tank on how much danger. A nano tank would be hard hit.

 

[OniTweak]

Does the yellow sting look like a feeding tentacle.

 

[tncoe18]

Yes, it looks like a feeding tenacle.

 

[CaPoNe]

Then id say its a feeding tentacle