Small red thing in clear tube at base of rock??

[Sand dollar]

Any idea what this could be? It appears to be living. It retracts down in the clear tube when startled. I haven't see it come all the way out but it will come to the top edge of the clear tube. Possibly has antennas, so tiny though so it's hard to tell. I will be watching when lights go out tonight.


Sent from my iPhone using Aquarium Advice

 

[Sand dollar]

This thing is definitely living and seems to be getting bigger. It retracts at the flash of the camera but is unable to retract as far back in its clear sac as before. It has two antennae that almost alway move around out of the sac that aren't really showing up in the pictures. I haven't seen it come all the way out yet. Any ideas what it could be? I hope it's something cool!


Sent from my iPhone using Aquarium Advice

 

[Katy410]

It may be a feather duster. They were all over my LR.


Sent from my iPhone using Aquarium Advice