What is this taking over my LR

[Silvabul10]

I have no idea what this is. I had a 5 year old stone fish die on me out of nowhere the other day. Then I noticed this stuff on some of my LR. I dont know if they have anything to do with eachother but I still want to know what this stuff is. It is not left over food. If anyone could help let me know.

 

[gear-head]

Are you referring to the white stuff. Can you describe it?

 

[phases99]

Are they curly white calcified shells? If they are they are a spirobid worm. I've got tons. They are harmless filter feeders.

 

[Silvabul10]

The stuff is flexible and soft. I have spoken to some guys at the LFS and they dont know what it is either. Can anyone tell me what this stuff is????