Any idea what this is?

[Mack12]

I’m very new to this and found this in my tank. Anyone have any idea what it could be and if it’s harmful? Thanks in advance! This is a saltwater tank. 

[daniejd]

Is it a freshwater or saltwater tank? Looks a bit like the larvae that come in on some freshwater plants. If it’s a saltwater tank, no idea.

[Mack12]

4 hours ago, daniejd said:

Is it a freshwater or saltwater tank? Looks a bit like the larvae that come in on some freshwater plants. If it’s a saltwater tank, no idea.

It is a saltwater tank, thank you for your response! 

[Tired]

Is it still alive? It looks a lot like an insect larva, and I'm wondering if it came from somewhere else and fell in there.

[Mack12]

On 7/29/2022 at 2:50 PM, Tired said:

Is it still alive? It looks a lot like an insect larva, and I'm wondering if it came from somewhere else and fell in there.

It’s still alive and moving around 

[M. Tournesol]

🤔 It don't look like a Pontomyia natans larva (I had some for 1,2 months when my live rock arrived)

 

 

 

 

[Mack12]

3 hours ago, M. Tournesol said:

🤔 It don't look like a Pontomyia natans larva (I had some for 1,2 months when my live rock arrived)

 

 

 

 

It does or doesn’t? I found it after I got my live rock 

[lakshwadeep]

Looks like some worm. If it has fuzzy bristles between the segments, it may be a polychaete, which are usually not a problem.

[Ohmegg]

Is this a shrimp tank? I wonder because of non traditional choice of rock and what looks like hair algae or cheto behind it. Do you know where that algae came from?