Weird Sand Tubes

[Toob]

They are showing up all over the tank - my goby carries them around sometimes.

They are all of similar size - perfectly circular and hollow inside like a straw. They hold their shape but crumble back into normal sand easily.

 

[sfin52]

It's a type of worm believe it's this chaetopterids

 

[Floyd-]

My bristle worms make little tunnels like that.

 

[ISpeakForTheSeas]

Yeah, lots of different worms and few different critters (including some amphipods) make sand tubes like that - the tubes and the critters making them should be harmless.