Acropora sweeper tentacles.

[Art2249]

Sorry the images are poor quality and you must look closely but here are some sweepers. You guys probably see this all the time but I thought it was cool.

 

[Billldg]

I always like it the most when you look at them with a flashlight at night. That's when the real tentacles come out. :)

 

[Art2249]

I always like it the most when you look at them with a flashlight at night. That's when the real tentacles come out. :)

yep

 

[Graffiti Spot]

Hard to see anything on my phone, are they filaments or polyps with a single long part? Viewing acropora at night is always fun but I haven’t done it for a while since everything’s in a tub.

 

[Art2249]

Hard to see anything on my phone, are they filaments or polyps with a single long part? Viewing acropora at night is always fun but I haven’t done it for a while since everything’s in a tub.

This happened during the day. It was filaments coming out of a polyp. I think. They look identical to very long sweepers that come off an lps coral in my tank. Just these are much smaller.

 

[Graffiti Spot]

Right on. I have seen the filaments from a number of things from feeding to stress. I am always more comfortable when I don’t see them because I never really see them on corals that are growing and colored great. Unless it’s making space to encrust or touching another coral or rock.

 

[C. Eymann]

I always like it the most when you look at them with a flashlight at night. That's when the real tentacles come out. :)

Thats also the best indicator of a colonies "happiness"

Particularly axial and further developed incipient axial corallites' polyps. (branch and branchlet tips)
Most species wont extend that polyp at all during the photoperiod as it is used almost exclusively for food capture as it has very low density of zooanxthelle compared to radial corallite polyps.
Stressed/unstable acropora wont extend those polyps at night.

When I see those on new acropora, esp ones that have recently come in from the wild/mariculture, I get a warm fuzzy feeling......

see what I did there?:p