Is this aptasia?

suikerspin

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Hey reefers

I recently put a piece of GSP in my tank. Now i noticed these tentacles coming from the backside of the gsp.

Is this aptasia?

IMG_3579.jpeg IMG_3578.jpeg IMG_3577.jpeg
 

EnterName

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It might be easier to see if you take photos under neutral/white light. Identifying just by a few tentacles is quite difficult though.

There are different Aiptasia species. Some are quite easy to deal with, others are insanely difficult to get rid of. I once had the really bad ones which killed many of my corals before I was able to find a solution that actually worked. I would just cut out the section of the GSP where it is sitting on, and get rid of it.
 

Reef Wizard Steven

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1781345211330.png

If you're talking about that, it looks like the small species of brittle stars to me, a fine hitchhiker, they are cleanup crew. It's a little difficult to see what we're looking at here, but that's probably what it is.


Aptaisia doesn't usually have parts of its oral disc tucked under things, it will usually extend it's body so it is fully in the water column when open, so you almost always see the oral disc completely, and not just a few tentacles. They are pest anemones, so they foot to a substrate or rock/surface, and then extend out into the water column. If you can see it from another angle, and it has a full disc of tentacles, and you can identify some sort of body that is going into the rocks or into the coral crevices, then you are likely looking at one.

My best guess, looks like brittlestar legs trying to filterfeed while keeping the most sensitive parts of its body tucked away safely. It's very possible it IS an aiptasia, but without getting a better look, hard to say.
 
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suikerspin

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I tried to make a picture in neutral light if it helps.

Thanks for all the fast replies hopefully its brittle stars i did use red sea dip before putting it in guess it doesnt get rid of all of the pests
 

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Reef Wizard Steven

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In my experience, brittle stars can actually survive a lot of dips. they will usually come out during a dip because it is not a fun experience, and if i see one, i try to save them. Not always the case though.

One of the biggest tells to me in your pictures is the bands on the legs (or tentacles). Aiptasia can have bands and stripes, but they usually aren't uniform in width and spaced evenly, they tend to vary in width and distance between the bands. One of the other tells, looks like the legs are textured, even though blurry, they dont look smooth. Aiptasia have smooth tentacles, despite having sometimes spotty or banded patterns, you wont see three dimensional texture. If it moves and doesn't appear in the same place, what would be the "oral disc" is never fully revealed (always tucked partially into the rocks or corals), and the tentacles are textured with even spaces and widths of the bands, then I'm 98% positive you are dealing with a brittle star.
 
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suikerspin

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Yeah its exactly as you described i also have located part of the disc tucked away between the coral.

Good to know what it is and actually one of the good pests. thanks for all the info and help
 

Reef Wizard Steven

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I tried to make a picture in neutral light if it helps.

Thanks for all the fast replies hopefully its brittle stars i did use red sea dip before putting it in guess it doesnt get rid of all of the pests
3851 is the most clear, and you can see the texture in the legs im talking about.

looks almost exactly like this photo, which is actually another post here about the same question

If this is what that looks like in person, which to me is what it looks like, then it is 100 percent a brittle star, no question

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