Extended tentacle on hammer coral

[Paulm7373]

Can anyone tell me why there is a single extended tentacle on my green hammer and why it's so much longer than the rest? I'm not concerned, just curious if it's a normal thing with hammers.

 

[bribo12]

That is a sweeper tentacle that if it comes into contact with other corals will sting the crap out of them.

 

[Freak1456]

It may also be testing the water. Did you just do a water change, Or disturbed the hammer an any way before you took the pic. I had a torch that whenever it got disturbed or I changed out the water it would contract. Then slowly would put out a tentacle. I always assumed it was testing the waters to make sure it was safe to fully extend.

 

[Paulm7373]

It's in a good position right now because it's a few inches away from the next closest coral which is that torch you can see in that picture. I also didn't do a water change or move or disturb it in any way just before-hand.