Can someone help identify these?

[brunyan25]

Hey all!
I recently was cleaning my pump and noticed these weird white caccoon like things all over my filteration chambers. I can’t find out what they are! Anyone know ? If you do know, are they bad? If so how do I get rid of them?

 

[IKD]

Most likely pineapple sponges. Harmless filter feeders.

 

[ISpeakForTheSeas]

Yeah, looks like Pineapple Sponges and Spirorbid Worms to me - harmless filter feeders.