I've never seen anything but normal polyps from my acros but last night my yellow acro colony had what looked like sweepers about 3/8-1/2" long. Lights were still on and they stayed out for a couple of hours. Does it mean the coral was "unhappy"? Nothing close to it. Frogspawn is a good 6" away and trumpet coral is about that far away.
That Acro is stretching his Acontia Filament, a little different than sweepers but he's protecting his turf. A lot of times you may notice it when introducing a new Acro into the tank. Here's a ReefBuilders article about it. http://reefbuilders.com/2011/09/26/oregon-blue-tort-acontia-filaments/
Thanks Greg and Shawn! The newest acro is the sapthulata from our meeting and it is the closest acro to him but it's almost a foot away. Can they detect competition that far away? Coral is a lot more complex than the "pretty plants" most non hobbiest see when they look in our tanks. Cool!
Not necessarily, it may have just got a chemical trace of something in the water column it took for a threat. Here's a video if that guys Oregon Tort attacking the glass http://m.youtube.com/watch?v=lcPD1Ajp75k
Wow! Mine weren't nearly that long but there were a lot more of them. Almost every coralite had one or two sticking out. Looks back to normal today.
I know this is about SPS but one of my LPS did that last week. My Lobo always has feeder feeder tentacles out but last week it had white, 2 inch long sweepers that came out of the middle of the body. I had never seen that before. Luckily he was about 4 inches from everyone else. Sorry to get off topic. John
