Good or bad?

[Reef Surfer]

I just put in some new live rock and found a few of these. I think they're some kind of worm. They are pretty much see through with a white tone. They swim by wiggling back and forth and are pretty fast. Anyone have any idea what they are and if they're good or bad?

 

[Reefkeepers Archive]

From this photo they almost look like lancelets, @ISpeakForTheSeas?

 

[Reef Surfer]

I just googled lancelets. I'm pretty sure that is them. Good or bad?

 

[WheatToast]

I just googled lancelets. I'm pretty sure that is them. Good or bad?

That's what I was thinking too. From what I know, they are harmless filter-feeders and are not long-lived in captivity.

 

[ISpeakForTheSeas]

Yeah, looks like Lancelets to me too - like WheatToast said, harmless filter-feeders. I haven't looked too in depth at these yet, but if you want to try and keep them, I'd suggest offering them a phytoplankton blend regularly (I don't know the specific needs of these, but Isochrysis, Chaetoceros, and Tetraselmis would be my go-to suggestions for phyto).

 

[Reef Surfer]

Yeah, looks like Lancelets to me too - like WheatToast said, harmless filter-feeders. I haven't looked too in depth at these yet, but if you want to try and keep them, I'd suggest offering them a phytoplankton blend regularly (I don't know the specific needs of these, but Isochrysis, Chaetoceros, and Tetraselmis would be my go-to suggestions for phyto).

I ordered rocks and sand from Tampa Bay Saltwater for my new IM 100. They probably came out of the new sand. I'm going to let the new tank run fishless for a month or so to build up the bacteria and copepods. I'll be feeding phyto for the pods anyways so the lancelets can eat this as well. I'm sure once my fish go in the new tank my pintail wrasse will devour the Lancelets in no time. He's a pig and eats anything lol.