What is this?

Starliah1111 · May 14, 2024

Hi guys, can somebody please id this for me?
Thanks

tzabor10 · May 14, 2024

The video doesn’t show

Starliah1111 · May 14, 2024

I had to try a few times to get it to work on my phone. I can try to upload again. See if it helps...

tzabor10 · May 14, 2024

Upload to YouTube and post the link

twentyleagues · May 14, 2024

Video works for me. It appears to be a filter feeder of some sort, you can see it catching particles out of the water column. Looks like live rock from the ocean? Could be a cucumber but I dont think so. It is more likely a filter feeding worm that I can not remember the name of. It isnt a vermatid snail. I dont think it is directly dangerous or detrimental to tank inhabitants. Lets see if @ISpeakForTheSeas might know. I would still upload the video to youtube that way more will be able to see it.

Starliah1111 · May 14, 2024

twentyleagues said:
Video works for me. It appears to be a filter feeder of some sort, you can see it catching particles out of the water column. Looks like live rock from the ocean? Could be a cucumber but I dont think so. It is more likely a filter feeding worm that I can not remember the name of. It isnt a vermatid snail. I dont think it is directly dangerous or detrimental to tank inhabitants. Lets see if @ISpeakForTheSeas might know. I would still upload the video to youtube that way more will be able to see it.

Awesome, thank you. Will try you tube tomorrow and post the link

ISpeakForTheSeas · May 14, 2024

twentyleagues said:
Video works for me. It appears to be a filter feeder of some sort, you can see it catching particles out of the water column. Looks like live rock from the ocean? Could be a cucumber but I dont think so. It is more likely a filter feeding worm that I can not remember the name of. It isnt a vermatid snail. I dont think it is directly dangerous or detrimental to tank inhabitants. Lets see if @ISpeakForTheSeas might know. I would still upload the video to youtube that way more will be able to see it.

Looks like a filter-feeding sea cucumber to me - the branches on the tentacles are generally a pretty good indicator there (completely seriously, though, if you know of a worm with similar, I'd love to learn about it).

Assuming it's a cucumber, it shouldn't be harmful unless something is picking on it/harassing it, or - in some cases - unless it's dying.

Long story short, sea cucumbers contain an ichthyotoxin (fish-toxin) known as holothurin in variable amounts dependent on the species: some sea cucumbers will release the toxin very easily (typically through eviscerating themselves and spewing their toxic organs into the water - most species can regrow them in a few weeks), others literally won't release it even if they're being eaten alive - so the level of danger depends on the individual cucumber and its species.

That said, incidents where these released toxins have caused problems in our tanks are incredibly rare (I only know of two or three "cuke nukes" currently, so they're definitely extreme outliers by all accounts that I've seen at this point), so I wouldn't be too concerned. Some people have had their cukes eviscerate without any issues whatsoever, but, to be safe, I always suggest having some premixed saltwater and carbon ready to run just in case your cuke releases its toxins into the tank.

Anyway, so just make sure nothing is bothering it (relatively few things in our tanks should harass sea cucumbers) and that it's well-fed (you can feed it phytoplankton like Isochrysis galbana (T-Iso), Tetraselmis sp., Thalassiosira sp., and Chaetoceros sp. or a blend containing multiple of these) and it shouldn't be a problem at all.

Starliah1111 · May 14, 2024

ISpeakForTheSeas said:
Looks like a filter-feeding sea cucumber to me - the branches on the tentacles are generally a pretty good indicator there (completely seriously, though, if you know of a worm with similar, I'd love to learn about it).

Assuming it's a cucumber, it shouldn't be harmful unless something is picking on it/harassing it, or - in some cases - unless it's dying.

Long story short, sea cucumbers contain an ichthyotoxin (fish-toxin) known as holothurin in variable amounts dependent on the species: some sea cucumbers will release the toxin very easily (typically through eviscerating themselves and spewing their toxic organs into the water - most species can regrow them in a few weeks), others literally won't release it even if they're being eaten alive - so the level of danger depends on the individual cucumber and its species.

That said, incidents where these released toxins have caused problems in our tanks are incredibly rare (I only know of two or three "cuke nukes" currently, so they're definitely extreme outliers by all accounts that I've seen at this point), so I wouldn't be too concerned. Some people have had their cukes eviscerate without any issues whatsoever, but, to be safe, I always suggest having some premixed saltwater and carbon ready to run just in case your cuke releases its toxins into the tank.

Anyway, so just make sure nothing is bothering it (relatively few things in our tanks should harass sea cucumbers) and that it's well-fed (you can feed it phytoplankton like Isochrysis galbana (T-Iso), Tetraselmis sp., Thalassiosira sp., and Chaetoceros sp. or a blend containing multiple of these) and it shouldn't be a problem at all.